I'm reassembling a 1947 Harley EL basket case and have a question about the front and rear brakes. I've noticed that in both cases, the brake shoe pivot studs want to move around in their backing plate slots, even when the anchor nuts and locks are in place and snugged tight. Is this the way the're supposed to be? I can see where allowing the studs to move would allow the brake shoes to "search" for better contact with the drum. Then again, maybe in my case the slots in the backing plates are worn excessively. I can shim the pivot studs so they're rigid, but I don't see any such pieces shown in the parts catalog. I'm stalled. A few words of guidance from experienced Knucklehead restorers out there would really be appreciated.