So my boss and I have two 1990 rangers at the shop, and we're planning on taking the standard trans out of the 2wd and putting it in the 4wd, and the automatic will be going in the 2wd.

Basically all I want to know is, is there anything extra that I need to know before doing this? I've heard from one person that you have to do something involving the ECU, but I have no idea. My boss says we just yank em out and pop em back in (and of course the clutch and shifter holes need to be cut)

Any information would be helpful. Thanks