A coat hook is an unlikely place to start comparing old trucks. But GMC’s 1983 pickup brochure gives it two whole lines: one hook for a Regular Cab, three for a Bonus or Crew Cab. The numbers stay exactly the same across Sierra, High Sierra and Sierra Classic.
The middle-of-the-range High Sierra has different seat-trim listings for two-door and four-door cabs. Follow its column down to the seats and the cab changes the answer again.
The details are in the interior section on printed page 17 of GMC Pickups, publication ADV 83-1, under “Standard Value Features on GMC Pickups.” Coat hooks appear first, with sill plates and door panels just below.
Start at the door
The sill plates follow the cab rather than the trim level. Black plastic is listed for two-door cabs in all three columns; bright metal is listed for four-door cabs across those same columns. A Sierra Classic two-door and a Sierra four-door therefore land on different lines of the chart, with the bright metal entry going to the four-door.
Rear-door ashtrays work much the same way. GMC lists them for four-door cabs under Sierra, High Sierra and Sierra Classic. Between the sill plates, ashtrays and coat hooks, the larger cab has already made several changes without moving up a trim level.
High Sierra makes you read twice
The seat upholstery is where the distinction becomes especially easy to miss. Standard vinyl appears under “All” for Sierra, but under “4-Dr Cab” for High Sierra. On the next line, the choice of custom vinyl or custom cloth is listed for High Sierra two-door cabs and for “All” under Sierra Classic.
So “High Sierra interior” needs a little more explanation here. The brochure gives its two-door and four-door cabs different upholstery entries. Reading only the trim name would skip that difference entirely.
The seats themselves get separate treatment too. GMC lists a full-foam, three-passenger front bench across all three trim columns. The full-foam, three-passenger rear bench is specifically labeled “Crew Cab” in each. That wording matters: the earlier coat-hook entry groups Bonus and Crew Cab together, while this rear-seat entry names Crew Cab alone. You can’t carry one row’s cab grouping into the next.
Mind the back of the floor
Even a seemingly straightforward floor-covering entry has a small exception. High Sierra’s color-keyed rubber mats and Sierra Classic’s color-keyed carpeting both exclude the Bonus Cab rear compartment. The chart doesn’t describe that rear compartment’s covering in either of those entries, so there’s no need to fill in the blank for it.
These are brochure listings, rather than proof of how any surviving truck left the factory. Page 16 also covers available accessories, and a dash in the page 17 chart shouldn’t be stretched into “couldn’t be ordered.”
Check the cab named on each line before comparing the trim columns. Bonus and Crew Cab share the coat-hook entry; the rear-bench entry names Crew Cab alone.
Source: GMC Pickups, ADV 83-1, printed page 17, with available-accessories context on printed page 16. Original brochure scan hosted by Old Car Brochures. View the original 1983 chart