I pretty much have exactly what you are asking about.
'66 Saginaw 3 speed, 3.08 12 bolt rear end, stock diameter tires on 16" rims.
I can go 70 without blowing anything up.
I cannot get out of my own way in first gear on a steep hill.
No free lunch with that combo.
I am in the process of swapping out for a T-5 transmission with 0.86 to 1 overdrive, and a 3.73 rear end.
Carl

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission