How do you get the snap ring out of reluctor?

I did exactly that, yes. To my knowledge the distributor was never apart before; but I can't be 100% certain nobody ever tried to gap it with a non-metallic gauge ... but I doubt it. What gets me is that it runs fairly okay one minute and then starts rocking and rolling and just won't idle.

About the 'chirping' sound ... that's exactly what it sounds like - a chirp. It happens more and more the worse rougher it runs. I think it's detonation. I plan to check the connections when the weather clears here - maybe tomorrow, but it is really weird.