Joe, I thought my explanation of the problem was pretty clear and, judging by some of the later responses, I'm not the only person having it. My red top's probably almost five years old but it's always been unreliable.
I'm not aware of any draws on my system but since it's pretty much been a garage queen forever while my resto is underway, I haven't had much road experience with it yet. Time will tell. In the interim, thanks for the head's up on the potential electrical issue -- I'll keep it in mind if regular driving doesn't keep the battery up. :-D
