I have a 1976 F250 with rear brake problems. The drums are worn down to the point they need to be replaced. It has a light duty brake system with an unusual rear drum size, 2" wide 12" diameter, which I cannot find a replacement for. Has anyone else had this problem? If so, what have you done to solve it? There are plenty of 2-1/2" drums available. I'm wondering if the whole assembly, plate and all, can be switched for a 2-1/2" assembly. Any ideas?