Install the high-performance brake pads into the caliper and lightly grease the threads on the caliper mounting bolts with a silicone-based grease. Trial fit the caliper onto the spindle. I found that it needed just a little more clearance in the lower part of the spindle for the caliper to seat right. Don't force it! If you can't get the bolts in, take the caliper off and you should see marks where the spindle was hitting the caliper. I got my right-angle grinder with a 36-grit disc and took a little of the casting off the spindle. Test fit the caliper again. It didn't take much and the bolts go in smoothly now.