Rim Choice with Dr. Diff's 13" Brakes

Since the kit is based on Cobra brakes, I think you'd be safe with Mustang Bullitt rims. A quick search turned up a variety of 17 & 18" sizes. Probably good with any aftermarket rim that uses the Ford center bore. Or you could leave a step on the hub to center the rotor, and have the remainder of the hub turned down to the Mopar diameter if you really wanted to.