I am putting in poly mounts. I got all of them loose except the ones right in front of the rear bumper. On one I got the whole bolt spinning in the floor. Do I need to grind the Herc. off and weld it up to keep it from spinning? Also on the other one I can't get the socket on. There is a metal piece around the bolt not letting the socket go on. I figure I will just get out a hammer and see if I can get the socket on with a little force. Does anybody know what that metal is connected too? TIA.