Towing a 68 on car dolly

Well the best I can figure is that the drum is coming in contact with the shoes on one side. Drum gets very hot, but I can wrap my hand around housing at outer bearing and not much heat.
Going fast enough for long enough will heat the entire unit pretty good.
All four corners got new shoes, drums, cylinders, rear brake cables, and hardware. When I tightened the wheels the rear drums came in contact with the backing plates and the frame of the shoes, not the not the friction material, the steel frame of the shoe was hitting the hub of the drums. Here is a quote from FBBO of what I had to do.


Thanks for all the replies. This is what I did:
.075 off the outer rim which helped to clear the upper ball joint
.075 off the inner rim which now clears the backing plate
increased the finished surface width by .125 so the drum clears the frame of the shoe

I suspect the Chinese drums are all different and maybe .125 wasn't quite enough to clear the shoes. Or I did it wrong by a hair. What I suspect is that the is some lateral movement of the axle on one side allowing the hub of the drum to intermittently contact the shoe frames.

Since I don't have time to mess around right now, and my cars are all over the country, and there is a huge possibility I will be bringing my old 340 4-speed Cuda home to roost, a trailer is in my future. Can't wait to see the fuel bill.