They make bolt in kits to put a 4.3 in Sami's.
Not back when I did it, I blazed my own trail.
EDIT: I just looked up the R.R./Suzuki Lightning conversion kit. Lol, I didn't even spend anywhere near the $3k they get for the "advanced kit". And that was with a rebuilt automatic trans, machine work on the block/crank/heads/rods, new pistons, bearings etc., and me assembling the engine. In addition to swapping in front & rear Jeep Dana 44 axles. For all of what was involved that I did and fabricated, R.R. gets over $6k.
Before I even got the idea for the engine conversion, I installed a 2" body lift, 3" suspension lift and 31" tires. The body lift ended up helping trans to tunnel clearance, and the suspension helped the diff to oil pan clearance. Junior (in the drivers seat) who was 3-4 yrs old at the time, is now 25.
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