i have a 1991 f150 with a 302 and want to drop in a 351 and what i need to know is will a 351 from the same vintage plug rite up the the 302 harness and work or is it not that easy

 

I have yet to swap an engine where the computer in it works like that. But I personally am not sure.

 

You will need the harnesses and computer 4 the engine you are swapping in

 

Wiring diagrams are the same for both engines, but that doesn't mean the harness is exactly the same. Some stuff might have a different connector, although I doubt it. More likely would be a sensor wire wouldn't reach where it goes. Definitely would want the computer.