a small and light boat with pointed ends
no way, car rear ends are alot smaller then truck rear ends. it will not work.
Most trucks in the 1980s did not come with 12 bolt rear ends. The most common was 14, but 10 bolt rear ends were also in evidence.
butts rear ends rumps etc.
When you open the hood, look where your windshield ends, below that is the rear of the engine.
Sounds like you're thinking of a kayak.
Simple answer is count the bolts on the diff cover. Generally 7.5 rear ends are 10 bold and have somewhat square corners. While the 8.5 rear ends have 12 bolts and are round.
All GM. rear ends have c- clips that hold the Axels in. Except 3/4 tons and up with full-floating rear ends.
eBay under Chevy rear ends