There is no kit that you can just go out and buy to turbocharge your 4.0 man. Its a total custom thing, requiring a great deal of fabrication, and parts sourcing, as well as in depth knowledge of what turbo charging is and how to make it work with your set up. Once you do that, the two biggest things I can think of is finding a engine management system(megasquirt, reflashed/tuned ford ecu, ect) to run it, and a transmission that isn't going to grenade once you romp it. If you look however there was a super charger available until a few years ago, believe that Whipple made them. They stopped years and years ago and even used ones are still worth quite a pretty penny.