Perhaps Oshkosh, as I've seen some stepvans with 6 lug Budd wheels with oshkosh chassis. I've heard of some from John Deere as well.
https://www.millsupply.com/stepvan-...-deere/chassis-parts-oshkosh-john-deere/

•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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