All 4x4s and everything 80 and up used the larger clutch disc. The flywheel is different, but I think everything else lines up just fine. You should be able to mix/match the parts as long as the flywheel, clutch disc, and pressure plate are all matched together. The only piece that meets up in there is the throwout bearing and I believe they are the same where it counts. The splines on the shaft and the pilot bearing are the same either size of clutch disc you use.
I've been thinking about doing a flywheel swap on my 77 when I put in the 5 Spd tranny, but I don't have it apart yet to confirm all this stuff visually.
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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
