If you post what you're looking for, we can probably tell what's a direct interchange, and what will work, but maybe not be 100% "correct" Things like arm rest pads are the same on all 66/67 B bodies, except some "high end" cars (like Satellite, Charger and Coronet 500) had 13" in the front, while the rest hd 9". 68-70 is a different pattern, but bolt on and work. Window cranks changed between 66 and 67, then again after that, but all will work up through the 80's.
Chrome trim on the exterior is usually different between all makes and models. Hoods are the same both years for their respective makes. Fenders are the same stampings, but usually the headlight buckets are different. Doors are the same all years all models exeept 4 door (and wagon) rear.
There are lots more but it would be a book to try to write out.