Doug,
It is true that the USA-GTS came with the same 7" front and 8" rear Campys as the rest of the USA cars.
It was/is real common for an owner to move the rear 8" wide Campy to the front, and add the then pseudo-over-the-counter 10" wide Campys to the rear.
Besides improving handling, it just looks better.
I think Gary Hall was one of the people that imported "tons" of 10" Campys, while some Ford dealership parts guys knew and would order/provide these wheels (not listed in the orange Ford parts book), other dealerships preferred to provide blank-stares instead.
I suspect you met the later type.
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