I was informed that sometimes Advent igintions may be faulty causing them to run intermittently right from the factory. However i would test the coil first and then switch to an NGK screw on type boot, this way you know you are getting good solid contact. Good luck, let me know. Also test the power wire on your Advent now that you have that one hooked up! Let me know.
Thanks again for your reply.
I've had this Advent ignition back to them once already and I know it is getting power. (This problem was identical with another CDI installed.) I think the problem must relate to a grounding issue with the spark plug leads or coil. I originally posted another thread about the leads seeming like they were grounding on the pipe and I think I may have been on the right track back then. I'm going to spray the leads with silicon spray and run a cooling hose or something over them (sealed at each end) to keep them away from other metal and water. I'll also pull the e-box (again) and make sure no other wires are close to the coil and that the coil is not touching the metal box (which is grounded of course).
I have another OEM coil on the way in case this new WSM one is no good.
I have searched and found other threads with identical problems that have not shown the final fix... If I get is sorted, I'll post the magic solution. In the meantime, others with experience with this condition please post any insight.