I had heard that there were bad results with Pertronix+ 6 Volt ANYTHING, and these posts made me remember some of the Studebaker comments (ie %$#$&@@#$!!!!!)
Shame, as it could seem to be a good way, IF properly designed and engineered, to always get a good hot spark on a 6 volt system. I have a feeling that they (Pertronix) didn't do the necessary homework and must have made six volts systems (and non-modern 12 volt systems) the cheap and easy way by just dropping the voltage with a diode or something, and everyone knows how well THAT works on 6 volt alternators and battery chargers compared to doing it right from the get go...ie, better than nothing but not what it should be.