My post was already getting too complicated without bringing 5spds into the mix so I figured I'd just stick to stock LUV facts.

The simple answer to the original question in this post is yes, but it wasn't clear if the motor was going into an 80 truck, or the trans was going into a 76.
I've got an 88 5spd from an Impulse ready to go in my 77 that is setup for a hydro clutch too. If you get into trans swapping, you just need to consider the clutch setup as a factor. Even then, it is not like it is impossible to change cable vs hydro, but it adds parts and work.
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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
