This is one I haven't heard discussed. I made a tail shaft extension from a donor 70's 3 speed and machined a tail shaft housing from 6" x 10" round cold roll(weighed 70 lbs when I started and 18 when finished), fabricated a rear mount and installed and S10 rear end. End result, original tranny, 3:73 ratio so the driving experience is still there but 55 is a reality. It all ready has one summers use on it with no problems.
