Been look'n through a 1954 "Chevrolet Truck Data Book, Specifications Catalog for Chevrolet salesmen" and the type truck example pages for vocational use show a 6403, 6103 and even a 5403 all with tandem rear axles. I wrote Chevrolet to find out ifin a vehicle archival information base is available to the general public. No reply just yet. If there is such a site, I will gladly w/great haste share w/all. Also shown was a "dually" 4 door "Crew cab" C.O.E. It is what dreams are made of.