BE careful with the imported truck axles, the rears in particular.

Check that the bolt pattern is OK for the wheels you want. Often what looks like 6 lug Budd are really a metric version that don't interchange with our 6 lug Budd wheels.

The rear axles usually have really low gears, and I think you'll want something in the mid to high 3.xx range. I also looked at the imported truck axles for the 61 F350 I had, and ended up with a TopKick front and Freightliner rear.

For gearing comparison the 61 F350 with 6V53T had 0.80 OD, 3.73 axle gears, and 38" tires. It weighed 10,000 empty and was comfortable to drive at 70-75, but would have been more efficient with 3.54 gears.
You won't have quite the power I had, so will probably want it geared the same as or just slower that that.
I like this gear calculator, last one on the page http://www.onlineconversion.com/bigger_tires.htm

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-