Still do not understand your thinking. The 350 engine stock does not put out that much horsepower. The figure I found was 180 horsepower vs 190 to 204. It also weighs more 575 lbs vs 440 lbs. Then the transmission weighs 125 lbs vs 77 lbs for my W58.
Wonders if the weight difference causes stability problems?
So really you have a government motors power train and I would think that only their speedo would work. About the one in my supra
, well there is the skinny! Saying it is a "little off" is being kind.
Have fun dude and be careful driving that Supra of yours!