Have a 1987 300e with a front disc that won't budge. I've taken the caliper off and removed the set screw with no problems and thought a few hits with the rubber hammer would set her free. No way no how even after applying heat and wd40. I noticed two metal hollow pins with a cutout that travel through the disc into the hub. I assumed these are for centering but I really don't know. I've searched the threads and found quite a few problems with rear discs that were solved with the use of a bigger hammer. Is this my fate also? I really don't like breaking things, usually ends badly.