Does the rotor hit all the cap terminals, or just some of them? Try blackening the cap terminals with a felt tip marker and spinning the shaft by hand, then checking them to see which ones are getting the interference. It sounds like the cap isn't fitting flush onto the distributor housing- - - -maybe there's a burr on the housing or it's bent in some way? How about the spring tension on the clips that hold the cap down. Final suggestion- - - -file the rotor tip slightly to prevent interference. There's supposed to be a tiny gap between the rotor and the cap terminals, and increasing it slightly won't affect the performance of the engine. That shouldn't be necessary, however. I believe you've got a fitment problem with the cap.
Jerry
