I would go back to the original 3.90 gears. With the 32' tires (compared to the original NAPCO 28" tires), you will be right where you need to be.
I can't help but feel sorry for the poor threads in your Model B for all of the times you have taken them out and put them back in.
Your rig doesn't need more fuel, it needs more RPM to perform well on grades. The only thing which will fix that with what you have is different gears (3.90)

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