from experience i would say you are turning the bolt the wrong way.. stop and look at it again... then picture that you are doing it correctly... i would have to bet that if its the bolt behind then you are doing what i did many of times.. turning one way, but the bolt need to go the other way.. its an easy mistake to make when trying to do it in a hurry..... if that not the case take a propane torch and heat up the bolt area without messing up the rubber in the caliper and then try.. someone might have put some locktite on it and it might be the kind that has to be heated to release the caliper bolt... i also had this problem on a
83 mustang.. broke three torx bits on it before i found out that i had to heat it up first... then it came off like it was hand tight....
