While like the others on Chat, I don't recommend the reverse polarity switch (RVS).
I have one on the Kingston Grey cabriolet only because it came with one originally. Grounding the distributor to the engine is rather tacky looking.
I'll always carry ab extra RV switch and length of wire that I can use to ground the distributer to the pushrod side pan, if the RV devises were to fail, as a backup also.
I don't think the RV switches were quite as bad as the reputation they have attributed to them. But still...
Best,
Charlie

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