Change from 4-speed to 3w/OD

I agree, my 71 slant duster has its 3 speed, fully synchronized.
And my 65 Dart was not. I rarely downshift under power. Roll off the gas, coast down to about 30 and apply the brakes then the clutch not too long after. Too many years driving my tool truck. ( auto trans though) I'm not hard on brakes either.