Help! I bought a 36 5-window and the front backing plates were inside the car. In putting the backing plates on ever thing is ok but when I install the drums they will go on but there is a gap of 1 inch between the backing plate and the inside edge of the drum. The seal fits up to the flange ok and the nut fits up fine. The backing has to be right because the mechial brakes linkage works fine. And the drums are wide 5s. What is going on here? Can any one help? Guy