If you don't have alot of mechanical knowledge, a well equipped garage to work out of, and additional transportation ......................... don't even get involved. The best thing to do would be store your present vehicle, start scrounging needed parts, while reading and asking questions getting a basis of information as to what to expect. If you have to hire a shop to do your work you would be better off buying one that is completed.
Talking about swapping a 350 is easy but there are alot of obstacles one doesn't plan and it all takes time. I switched a four to a six and to say the least encountered more problems than I ever imagined. If I charged ten dollars an hour it would be a mighty expensive machine. If you enjoy a challenge it will be enjoyable. Not all projects are done to get to a qualified point. " I bet I can do that " will certainly get your brain to exploring alternatives. Have fun no matter which route you venture.