Well, I have been working on taking the rear shoes of my 1 Ton, and they are Huck brakes. What a horrible job it is getting the main pivot pin and pin lock off!!! Anyhow, for those who may be interested, Chevs of the 40s carries the correct "E Clip" for that main pin. They describe it has " 1 3/16" O. D. " and that makes no sense at all. The actual diameter of the groove is around 3/4".