Re: 2 SPEED REAREND
Not sure specifics,I have only seen 2spd rears in 1-1/2 ton and larger and they have a fairly large gear split that a SB might not have enough torque to make work.
Not sure exactly what you want to achieve, a 4spd tranny may work better
As for drive train swap in the same size vehicle with only a few years difference should be bolt in,350 and 400 if both small blocks are the same,so moving tranny mount may be only issue( or it may bolt in)
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