I would think that it would have definitely had matching rims on all four corners from the factory. About the only factory Fords I'm aware of that came with wider rims in the rear were the 'Super Camper Special" Dentside trucks.
The gentleman who passed away probably upgraded to wider rubber for better stability with the camper. Just my best "Slickitis" guess on the matter.
Oh & Custom Cabs could be ordered with chrome or painted front bumpers...grilles too, for that matter. It's really hard to nail down a true "package" when dealing with the CC options.
I originally thought that the CC package automatically got all the shiny stuff, but I've seen many through the years that definitely weren't born that way. I'm pretty sure a buyer could add or delete pretty much anything on the list when he was ordering his new truck.
This one looks like it's a beauty, I hope you bring it home.

BTW you guys, I also spy an argent front valance (stone shield).

My "Slickitis" affliction began here...
66 F100 CC/
65 F100 CC/
66 F250 CC
If it starts to rain, they'll tax the splash.
If you want to fish, they'll tax the bass.
If you plant a yard, they'll tax the grass.
If you don't play nice, they'll fine your *$#!