To all who might have this problem occur. Just get a right angle drill and a left hand direction drill bit ($2.50) and drill out the head of the screw, the rotor comes off and the screw remnant can be removed by hand because there is no longer any tension on the screw. Had to do this for two of the screws, they were corroded in place because the rotors seem to be original and never removed in 10 yrs or more. Steve