I used the rear disc brakes off a 1985 eldrado cadallic. they were cheaper than the trans am disc brake. I made the bracket to mount the caliper to the rear end housing. easy setup, bolted a 1/4" c plate to the rear end mounted the rotor marked where i wanted the caliper. drilled the hole to mount it welded two nuts on the back of the bracket. i put 25,000 mile on it no problems.