Do it once and do it right has always been my proponent. It seems to me that you have very little skill with modern vehicles(1980's - Current) and am stuck in a mindset that's 30+ years old. I'm not saying this is a bad thing, but doing a swap on a more "current" vehicle is a lot more detailed than you think.
Like others have said, STOP and do your research, LOTS of it. We all started out knowing absolutely nothing at some point in time, and over the years we've all learned various things and life, automobiles, and jeeps. If you think it's as simple as removing the old engine and putting in a different one(regardless of motor) with a few adapter plates, than you're going to have a VERY difficult time with this project and getting it out on the street/trail.
A motor swap can consist of an investment of thousands of dollars to be done once and done right. Your best bet may very well be selling your TJ and either getting one with a 4.0, or getting a CJ/YJ if you are that convinced fuel injection is something you don't want to deal with.
"Courage is being scared to death... and saddling up anyway" - John Wayne