Both are torsion bar IFS built pretty much the same. here are some differences, like the lower control arm, torsion bars, mounting points for the front axle and so forth. It all depends on what you are going to do with it if the differences matter. If you could give some info on why it might matter that would help. The basic frame is the same, so if you were going to build a SAS 4x4 truck you could start with either. If you want a 2WD V8 monster, it would save time and effort to start with a 2WD truck. Even after pulling the front axle, there would be hubs and spindles to worry about sealing up or swapping out.
So, tell me more about what you have in mind and I'll do my best to give you some idea what could get in your way.
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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)
MEPR: Man, my 4x4 makes all other LUVs look good
