I am no guy... you know like some "Guy" or anything, but I do believe that is a F350 or what we call, us non-guy ( guy means like truck expert) a, One Ton Ford .
The F350 1 Ton.. came with several options one was a Dual Package rear end, the truck was called a camper special..? , and was meant for a fifth wheel trailor or a cab over camper. Long hauling lots of weight. Hence the need for dual support.
The truck used the exact same axle wether it was runnin the dual wheels with the side fenders on, or if the fenders were off and the truck was running just two rear tires.
A different axle than a standard two wheeled Ford 350 of that year, to accomodate the duals.
I believe they purposely lifted the bed to accomodate the dual set up, but stayed with the same frame that all Ford trucks came with so.....this could all be original.
The same bed is the same for the non-dual the cover fenders are a bolt on over the sides of the bed, a factory option..
I am no Guy tho i'm just say'n...
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