If you look at the last page of their catalog, you will also find that they have 6v negative and positive ground ignitions:
http://www.pertronix.com/ 1167N6 1941-1953 216/235 6v negative
1168N6 1954-1962 235/261 6v negative
Most likely, the two parts differ in the size of the distributor-shaft cam (no need for filler).
Pertronix also has 1.5 ohm coils that work with the 6v system.
What they do not have is the recommended (by them) zener diode that protects the system from overload/spikes/surges (supposedly the most common cause of failure). If anyone know where the following diodes can be purchased in lots of 1-25 (not a lot of 1,000), please post the company here.
5KP20C
5KP20CA
5KP22C
5KP22CA
As a back-up, in case of failure, carry a set of points/condensor and installation tools.
Tim
