[Willie Krash]

It may be worth a note that if the generator isn't the same polarity as the car it will be in series with the battery.
Early regulators and as far as I know cutouts (reverse current relay) used different metal on the points. This was to equalize wear and avoid pitting.

Now for the can of worms and I will not defend it nor try, in the recent trade magazine for rebuilders they attempted to answer the age old question...pos/neg ground.
They explained that all coils are positive ground (secondary) regardless of the battery and that spark plugs are built for pos ground..!
I'm still thinkin on this..