I have a 2001 screw 2wd, I want to convert it to a 4wd. Now before you go and say just buy a 4wd know that I have a donor truck, and if it can not be reasonbly done I don't require a 4wd. I would like to also put in a manual transmission with a dogleg 4wd instead of an automatic with am electric shift 4wd (I will need to buy a transmission).

 

you will need to buy a lot of stuff

sounds like an interesting project, hope it works out
I think about the easiest way to convert to 4x4 is to swap body to a 4x4 chasis as the 4x2 frame is different.