I've measured it but I can't get a consistent measurement. I've looked around with google trying to find the info to no avail. My car is a 68 Torino, although I think a 68 Mustang would be the same, is this correct? Using a Caliper I get measurements in the range of 2.41 - 2.43 inches. Those measurements don't seem like they are going to get me real far on trying to get a something made for wheel hubcentricity. Can someone tell me what the hub dimension should be or even just what the inner diameter for the ring should be?