there are some differances in electronics over the years and application--
Cranks--2 different reluctor wheels at the rear
some have cam dealies
some drop cylinders for fuel economy
some throttle bodies are drive by wire(electronic)

sooooo--if you are looking at a used (take out) at least get the ECM from the vehicle and possibly the engine wiring harness

look at the different vehicles to see how the accessories are mounted--AC, PS, ALT