I'm in the process of installing the rear disc brakes, of a Baer Serious Street setup, in my 69 Camaro. According to the instructions, the rotor and caliper housing must have a minimum of 0.030 inch to a max of 0.090 inches of clearance. Baer recommends using shims between the "intermediate" bracket and caliper to get the correct clearance. Has anyone done this? Where can I get these caliper alignment shims? Thanks.