Looks to me that you could use the 3 bolt cam gear right on the single bolt cam - and then get your single pulse signal...
What I'm thinking is that if the pin is in the right place - or at least the same place on both gears (or perhaps you could drill a new one?) -- so that they're located correctly.... then weld up the 3 bolt holes - machine 'em flat - and ream/bore out the single hole to accept your single bolt...
Am I an idiot or what.... ??
