Looks like normal Eaton axle and hubs.
The actual hub pilot diameter where the wheel fits on the hub is larger than where you show the measurements.

Depending on brake size you might have to have 19.5” wheels if you want tubeless. My 1951 1 ton dual only just fit 19.5” wheels, they’re less than 1/4” from hitting the drum, a 16” wheel certainly wouldn’t fit the rear of my truck.

•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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