Originally Posted by D'Ecosse
are those actually indeed 15" @EchoBravoSierra ?

And they still fit?
Of course the riveted flange of the early wheels and shape of the center piece is what is causing the issue so maybe the later wheels just have a quite different back plane, so even 15 fits?
I'm measuring about 7-1/4" from hub center to the outside of caliper - the problem with the wheels I have is the inner web of the wheels - just spacing the 16's out a little bit is enough to clear them

Yessir, fifteen inch wheels. The hoop diameter isn't where the interference with the caliper is, it's at the back of the center, or the curve where it transitions to the hoop, best I can remember, at least with these particular disc brakes (based on stock 70s-80s GM components). For grins (and science) I recently had a buddy bring one of his 15" artillery wheels over to test fit. It went on fine until the lug nuts got hand-tight, then the back of the wheel center hit the caliper.