Awesome! that will be a cool build. I did the 5.3 LS conversion with a 98 jeep TJ. No issues at all. Now if you are rocking it, yes upgrades to the axles should be considered, but if your jeep is already a rubicon, chances are you have dana 44’s and if it had the 4.0l you will be on your way No upgrade needed, Fuel pump axles and lines will work just fine. lots of wrenching but well worth it.