A lot of research was done prior to the build to determine if going 4L60E or 4L80E was practical. To me it seemed like 67-72 4x4 guys going the computer controlled transmission route were fighting pretty hard to make it happen. My previous project, C10 with LQ4, used a 700R4 so I already knew how to strip the transmission wiring out of the harness. With the K10 a lot of other considerations crept in: front drive shaft to transmission pan clearance, transmission to transfer case mating, transmission tail shaft swapping, etc. Since the Mexacali Express will only be driven about 5k miles/year overdrive just didn't seem like it was going to be worth the trouble and money.
Note: If your intent is to use a non-computer controlled transmission in front of an LSX engine LQ4's out of GM vans is a nice way to go. The vans retained cable actuated throttle bodies until '07 according to reports which makes the swap less painful when dealing with cable actuated transmissions like the TH350 and 700R4. Later model years also means you're more likely to find a lower mile engine to use for your build.
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