The casting for the brake backplate flange/spring hanger appear to be brazed and pinned to the axle casing - two 5/16" dia. pins at each end of the axle. Does anyone know if the pins are structural or just to located the parts for brazing? I ask as one of my pins is missing causing an oil leak and my first thought (easy option) was to seal with mastic!
I would prefer to replace the pin personally. Although I think they were originally a location marker - they do add to the stiffness of the overall casing.
Some years ago we re-built the NA's rear axle and I actually welded the end housings in place. But I left the pins in place as well.