There was a 4-wheel version of the 3800, which was used mostly for a long wheelbase pickup. If the truck was originally equipped with dual rear wheels, the front hubs would have included a heavy spacer between the brake drum and the wheel mounting surface which moved the track width of the front wheels out about 2 inches on each side. This allowed the front hubs to run the same deep-offset wheels that were necessary for dual rear wheels. Unless someone has changed the front hubs at sometime in the past, the truck had 4 wheels originally, not 6. My 1959 3800 was set up with a 10-foot flatbed and dual rear wheels. It had the extended-width front hubs.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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