for what its worth, before i got into these MJs i could barely check my own oil ( ok , thats a bit of an exaggeration , but not too much), but after being around this forum for a couple of years i am pretty sure i know exactly what i would do in your situation.
i would find out the gear ratio - you probably know it by now but if not find out. -then i would phone a larger auto wrecker and ask for a chrysler 8.25 from an xj cherokee with that gear ratio and either go and get it or have it shipped. then i would put it in your truck and take it to a reputable mechanic along with 2 new perches (that are about $10. each). leave it while you go for lunch and then go pay him his 2 hrs or whatever and thats it. done.