OR... it could be that my cotton-pickin' negative battery terminal screw was backed out and hanging on by about 10 degrees worth of the very last thread. My new theory is that that tenuous connection allowed enough amperage to keep the light on but not near enough to consistently deliver a spark. Tightened it up, checked my other connections, started and idled fine. Just to be sure, I checked the resistance on the pick up coil and got 600 ohms. I guess I'll figure out on the way home if the battery terminal was the sole cause.
Anyway, thanks for the input. I at least got a good education on my ignition system today.
