I've seen the AW4s swapped into TJs in the past, but I don't know what year they used. If you want information there's a guy on greatlakes4x4 that did this swap and really liked it. I liked the auto in my XJ for rock crawling. You have a lot more control on the way up, but the downside is that you have to use a lot of brakes on the way down since even if you have it in first it will shift if the RPMs get too high. With all the work you just put into your belly up I would look at transmissions lengths and if the flatbelly would give you trouble switching to an automatic.