Why 2JZ on a 4wd truck? If you're actually going turbo on a 2JZ, you'll be around 350hp with a modest build, way more than necessary if you plan on wheeling it, and a turbo on the trails is really pointless, unless you're into rock racing!
But, if that's what you're looking to do, then you'll probably want to look at driftmotion's website for trans adapters. I don't recall if the '91 still used the w56 trans or the R trans, but just research "2JZ to W58" or "2JZ to R134", google will bring up lots of options for either trans.
As for the piping, good luck with that! There's not much room to mount an intercooler, and with any straight axle setup, you'll have issues getting all the piping out of the way of articulation from the front axle. I've seen a 7MGTE swap on a 90's truck, and every time the guy turned right, it would knock off the turbo pipe from the intercooler.
If you're keeping it IFS, then it will be easier to route pipework, but still not much room to mount intercooler up front, along with electric fan and radiator. Don't ask me where you'll put the a/c condenser!
Cost to do a swap like this will be pretty close to 8 grand if you do it right and find no problems with a 2J motor. Rebuilding it will be another $1500+ if you find any compression issues, and most of the 2J's out there now have been pretty well beat on. Those that aren't beaten to death are still on the road. Lots of fabrication to be done, so get ready to do a good amount of welding and bracketry.
Been there, done that, now doing a 1UZ in a MKII supra, as well as another 1UZ in my '87 truck in the future, just the rebuild on the first engine has me at over a grand in parts and some machine shop work. I haven't even started on ordering the adapters and other stuff in yet!
