Welcome,

Not a silly question at all, all options are worth considering.

This thread explores the original hub and adding disc option for a 46 Big Bolt, may have something in common with your 38?
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=891012&page=1

I've tried/considered other ways myself, the P30 parts option is the one I like most at this time. With more or less work most of your options will work in the end. The brake capacity, reliability of the system, and availability of parts are all worth considering.

My goal in finding a suitable solution for the mainly AD trucks (but most any year with 1.109" kingpin) is something that is factory for another vehicle (for reliability) and takes very little fabrication or machine work, ideally none. What I've come up with for the dual wheel trucks requires a spare later model (P30)axle for parts and you need to ream or bore the existing P30 bushings out to then press the original size bushings inside them (or turn adapter bushings). The rest is just swapping parts, no disc adapters or caliper brackets to fab.

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-