Hi. I have a 1986 f250 4x4 that I want to swap a 12v Cummins engine into. I'm wondering which year engine is the best one to do and out of which vehicle like a bus or a pickup is better/easier to make work in a ford. I know these engines are all mechanical and simple but some people have been saying that intake and exhaust manifolds are different between some. Can someone clarify this for me. And also how hard would it be to use a dodge tranny in the ford or would it be better to get the plate adapter for the trans already in my ford. Thanks.