That's probably just some epoxy holding that hall sensor in place. You should have no trouble getting it out, and replacing it. Ralph (RcIgnitions) 928 635 2455, is who likely converted that engine to EI, per TKG's comment above. You can call Ralph for ignition parts, or PM TKG above to get what you need. I had a hall sensor go bad in a hub like that one, though it was fixed...and it's no problem to remove and replace them if necessary. You can re-use the adjustable wheel using the readily available autoadvance units, just find and set the ignition at 28-30BTDC, secure the wheel so it can no longer adjust. Just find an imobile place to anchor the ball link at the correct timing location. Really, every concern will be put to rest if you get either Ralph or Terry on the horn.