clearing big wheels?

Your right on the wheel center hole being to small. I've been using Crown Vic 16" wheels and tried a late 80's Lincoln LSC 16" wheel and in both cases only a minor amount of material, about a 16th (.06) around the circumference, had to be removed for them to fit over the Mopar hub center. It was a lot easier to grind off the soft aluminum than machining the cast iron rotor.