I think 8 lug on a big truck is sort of wrong, and on a COE with lots of front axle weight...?

The later model P-30 8 lug axle with disc brakes is the same as the 10 lug version except for hub/rotor and caliper bracket, they use a smaller diameter rotor than the 5/10 lug version. So it's a pretty stout front axle beam and bearings but not as good on the brakes, but still pretty large disc brakes.
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=725027#Post725027

I would not use an 8 lug axle from the older trucks, they're relatively wimpy compared to the axle you'd be removing.

•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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