What year and model truck?
You can probably use same size front and rear, and probably fit larger than stock. Although a 7.5” wheel is getting a little wide for these old trucks, 6” rim and tires that fit a 6” rim might fit under the fenders better.
Won’t be original anyhow, so as long as the tires and wheels fit you’re good to go.

•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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