Jim,
As you know, my disc brake upgrade used GM spindles, calipers, brackets and wheel bearings (courtesy of OPH
) and new GM type rotors for 70/71 GTO. The spindles & brakes lined up perfectly and the new ball joints on the control arms bolted together perfectly with the spindles because they were standard matched GM parts. There were no problems with finding bearings to fit the hubs & rotors either because they are commonly available. The Rally 1's were obviously no problem either. FWIW, when I took the car to be aligned the guy used standard specs and had no difficulty due to the geometry with the discs and the wheel width was the same as before.
From personal experience, you don't want to get into the job and waste time re-engineering things. Who knows, these hubs might actually
save you some hassles. Do you know anyone else who has used them
.
Tim
http://kurtspontiac.homestead.com/TimSimpson66GTO.html