Magnum 500'd A-bodies??

I was planning on running 14" Magnums on my '75 Scamp - until the right front was rubbing the caliper. I carefully ground down some material from the caliper and it cleared, but it was too close for comfort for me. Now I don't know if that right caliper was relplaced because the left side did not rub. 14's are tricky with disc brakes. I know other guys haven't had an issue with 14's. Aftermarket 15" magnums should clear no problem.