This was the most disturbing thing about this installation which did not have anything to do with the caliper. The small bushing that allows the caliper to \"float\" on the mounting bolts crumbled at about 30 ft. lbs. of torque. I thought I had stripped the caliper but basically the metal just gave way. I used the old ones which were actual steel. I have no idea what the other metal was. If the bushing distorts under tightening the caliper will freeze up and braking will be very poor.