Hi deanomartini,
First of all, welcome to the stovebolt!
Here's a suggestion. Why not change the gears in the rear, PATRICKS has the sets and they are cheap enough. You could also use a manual transmission swap (assuming you want to keep the manual trans.) to a three speed overdrive Chevy trans from the 50's. They are available and reasonably priced.
Just an idea and my 2 cents worth.
Again welcome and good luck with your truck.
Dave
