RPO ZJ1: 1976-77 Custom Two-Tone Interior

The automotive industry was challenged in the 1970s when performance, horsepower and cubic inches were no longer options available to buyers. Sales continued, despite the ablation of muscle-car options, as the menu of comfort, convenience and power-assist options expanded. Corvette learned that buyers sought America's Sports Car for a leisure ride in a classic and ordered convenience options and cosmetic features in record numbers.

In 1976, RPO ZJ1 a custom two-tone interior option was offered, and again in 1977. However, it will not be found among the Regular Production Options (RPO) listings in the NCRS 1968-82 Corvette Specifications Guide nor black books. The 1953-82 Parts and Illustration Catalog listed the RPO with a brief description for ZJ1 as ZJI Custom Interior – Two Tone. The 3rd edition of the 1975-77 TIMJG addresses ZJ1 and related codes that were printed on buildsheets (GMAD manifest) and the Monroney label glued to the window. This article expands that discussion and provides additional illustrations, describing the process in detail from the dealer's order to production and the documentation that confirms the final build for a ZJ1 custom two-tone interior.

What makes ZJ1 a custom two-tone interior?

The two-tone interior RPO ZJ1 is a curious option that piques Corvette enthusiast's interest when seen, studied or judged. Until recently, it was virtually unknown except to those owners who enjoyed showing off the oddity to fellow enthusiasts. Corvette enthusiasts are generally surprised to learn that GM Chevrolet built this interior-color combination and it is referenced in GM Chevrolet Corvette Dealer Order Guides.

The recommended interior-color combinations varied between the two years as shown in Tables 1 and 2. The interior color selected by the buyer is the primary trim package (instrument panel, carpet and trim), and when ZJ1 is ordered, selected interior components become the accent color or white. In 1976, seats and door panels are white while in 1977, the headliner is included with the seats and door panels.

Figure 1: 1976 ZJ1 and firethorn/white

Leather seats were standard for the first time in 1977 but Corvette buyers could opt for a cloth-leather combination at no additional cost. The two-tone interior option meant three seat/trim combinations available to the buyer at no cost in 1977. However, in 1976 buyers had to fork out an additional $164.00 for Custom Interior Trim. The dealer order guides included order codes accompanied with a description for either leather, cloth or in 1976-77, the two-tone optional interior. Sales order codes were quite different than production or build codes and the buildsheet called out build codes to direct factory workers with installation of the buyer's primary trim selection.

The Sales Order: RPO ZP2 Process Option

When ZJ1 was ordered, an additional RPO, ZP2, was called out and printed on the manifest (See Figure 2). ZP2 is a process option, or instruction to either a zone office or the factory. When the box option was checked for the two-tone interior, it took an override by zone office (RPO ZP2) requesting confirmation by the buyer's dealer before the factory would proceed with production for the ZJ1 order. The ZP2 process code printed on the manifest in the RPO column. This was, and remains, a common Corvette practice when buyer's requested special orders or non-recommended color combinations. The 1977 Corvette Color & Trim Selection chart in the Dealer Order Guide included a note referring to both recommended ideal combinations and dealer confirmation:

Please Note: The exterior and interior combinations shown in the chart below and designated as recommended, represent the ideal combinations. Those that are shown as acceptable (A), are attractive, but less desirable then the recommended combinations. Orders for additional combinations may be submitted, provide the dealer initials the appropriate order form box (ZP2), as verification that the requested combination is definitely desired.

Figure 2: 1977 Buildsheet with ZJ1 and ZP2

The ZP2 Process Option was called out for either non-recommended color combinations or other buyer requests that depart from routine ordering. In 1977, ZP2 was also called out for Corvette orders built and shipped to Canada. It instructed the zone office to follow-up with the dealer and confirm that the order was intended for Canada. As the note indicates, the dealer initialed the order form to confirm the buyer's selection. Other "Process Option" codes were used throughout the GM system in the 1970s as production and/or ordering notes to bring attention to deviations from a base production unit. Another instance, in 1978 process code YK6 instructed the factory to ensure Z78 Pace Cars shipped with red-stripe RPO YJ8 aluminum wheels.

Figure 3: 1977 ZJ1 and blue/white

Building RPO ZJ1: Production Codes

Tables 1 and 2 show the code sets, both sales (dealer order code on window sticker) and build (manifest) for the two-tone interior color options. The dealer order code (sales) designated either leather or cloth seats by color. The code printed on the window sticker to the right of the trim RPO code on the description line (See Figure 7). The color code called out the color for the trim package that included, seats, carpet, headliner, steering column, steering wheel, seatbelts, etc. As noted earlier, when the zone office received a Corvette order from the dealer with RPO ZJ1, the process option ZP2 was called out with an instruction directed to the zone office to follow up with the dealer to confirm the buyer's wish before proceeding with scheduling the order with the factory for production.

The ZJ1 code called out a third trim option code associated with the two-tone interior, or the WH2 preceded by the trim code. Box 77 of the manifest documents the color trim code and a color fabric code. But when ZJ1 is ordered, the fabric code WH2 is called out for the white accent pieces. For example in Figure 4, box 77, blue is interior color code and normally would print 271272 (blue leather). Or if cloth was ordered the box 77 code called out 27127C (blue cloth). However when ZJ1 was called out, in place of the 272(C) the 271WH2 is called out in Box 77 (See Table 2).

Figure 4: ZJ1 Manifest; Box 77-271WH2 code

Table 1
1976 RPO ZJ1 – Interior Color & Trim Codes

Table 2
1977 RPO ZJ1 – Interior Color & Trim Codes

In 1976, color options were black/white, bluegreen/white, dark brown/white, firethorn/white and smoke grey/white. In 1977, color options included red/white, blue/white, smoke grey/white and buckskin/white with red appearing to be the most common color choice.

Documenting the ZJ1 Build Option

To confirm a ZJ1 factory-built custom two-tone interior requires several documents and differs by model year. Both years, the window sticker lists the AWxx code while the buildsheet references the trim codes and the WH2 code. In 1977, the trim tag, window sticker along with the manifest all reconcile and confirm the ZJ1 option.

The RPO ZJ1 Trim Tag

1977 Corvettes built with ZJ1 are easier to document than those built in 1976. In 1977 the trim tag was stamped with the ZJ1 among those Corvettes equipped with two-tone interiors. This practice appears confined to the 1977 model year. Evidence has not been found where 1976 trim tags with a two-tone interior had the ZJ1 stamp on the tag as seen in 1977. Note ZJ1 in the upper left-hand corner in Figure 5. This 1977 was built with white paint (10L), the smoke grey interior (152) and white accent features.

Figure 5: RPO ZJ1 152 trim tag

Figure 6 illustrates the trim tag for a 1977 with yellow paint and a non-recommended white on buckskin interior. This practice is typical of Corvette to build the vehicle the customer orders and continued into the twenty-first century. For example, when millennium yellow was introduced in 2000, and the buyer wanted the Torch Red interior, zone office would intervene and confirm with the dealer that indeed this was the buyer's preference.

Figure 6: RPO ZJ1 on trim tag

Figure 7: Trim code RPO 712 with the dealer code AWF2 for white leather buckets and firethorn interior

Retail & Dealers Invoice

An owner, especially a second or third owner could be confused when depending solely on either the retail (window sticker) or the dealer invoice to confirm ZJ1, especially in 1976 without either the buildsheet or ZJ1 on the trim tag. The ZJ1 was not printed on either sales document. Rather the interior code and the ZJ1 custom two-tone dealer code were listed on the window sticker as shown in Figure 7. Look closely at RPO 712 and compare the trim description to its right. Note AWF2 WHITE LEATHER BKT/DR FIRE ACC where AWF2 refers to the white leather bucket seats (Table 1) and DR FIRE ACC refers to the interior trim or firethorn in 1976.

We see here that to confirm a ZJ1 factory-built custom two-tone interior requires several documents that differ by model year. Both years, the window sticker lists the AWxx code while the buildsheet references the trim codes and the WH2. In 1977, the trim tag, window sticker along with the manifest all confirm the ZJ1 option.

Summary

Chevrolet teased buyers by offering ZJ1 to those who sought a Corvette for its comfort, convenience and cosmetic features. In fact, the rationale for Corvette resto-mod enthusiasts is the addition of convenience options combined with style and the power teams of C4 or C5 model years, or the best of old and new! The mid 1970 Corvettes represents the transition from high-performance of the early years to the leisure-seeking enthusiasts of later years. Corvette enthusiasts love their horsepower but the early-C3 era were accompanied by noise, cabin heat and lead-scented emissions. Enthusiasts also learned to enjoy those late-model C3s despite the low horsepower but appreciated the quiet ride, climate-controlled cabin and reduced emissions, both scent and discharges!

Chevrolet Corvette model year 1978, as well known, expanded the offering of special cosmetic schemes (paint and decals) with the B2Z Anniversary Paint option and the Z78 Limited Edition Pace Car. In 1982 Corvette, with a last gasp effort and final salute to the C3 era, offered enthusiasts the Collector's Edition with its ever-so-popular hatchback. The intent of this article is to instigate a discussion among 1976-77 Corvette two-tone interior owners. While considerable study has produced what is known to this point, much remains to be confirmed by those owners whose Corvette sports this limited color-interior option. Hopefully, this discussion inspires owners that the time has come to show Corvette enthusiasts these special builds.

Note: The author and the Corvette Restorer thank the many owners who have shown their ZJ1 Corvette and shared documentation to better understand this option. Special appreciation to Bob Beck who was the first NCRS member who stirred this author's interest with, what at the time, was a relatively unknown build option.

Tom Russo, NCRS Member# 22903
Hunt4cleanair@earthlink.net
Publication Pending: Submitted 08Feb22 to NCRS Corvette Restorer