Wilwood again - I can't win!

I put the caliper on one side, and found that the rotor was dragging on the shoes. So I wanted to pull the caliper off and put another shim in.

I couldn't get the bolts out. They would spin and spin but not come out. Finally I was able to get them out, but they came out with the threads from the inside of the caliper bracket!

WTF?