50 years ago I drove a full manual (reverse) valve body on the street (E-booger and I converted the VB using the Chrysler kit). It was a misery to drive in traffic, even with 4.89 axle.
1 drop of rain makes the car undriveable. You can't shift unless the steering is centered, the car will climb a tree.
My 520 hp turbo Lexus's A340E auto trans has a spark retard during shifts to save the friction materials as OEM (25 years ago).