I was half way on to a disk swap.. I should have too. DAMNIT. Possible the backing is bent, would this not have affected the old shoes as well though? I dunno. The shoes pivot area did not looks excessively worn or anything, its an odd one.
Possibly cause the old shoes were worn?
I have mk3 backing plates/spindle/hardware/shoes/cylinders in my garage.. but drums are $55 a piece!