I recently acquired from my grandfather his 1929 Imperial Sedan. Sometime ago it was coverted to a 12v system. What would it take to convert it back to 6v?

It all depends upon how far he went with the conversion. If he didn't change out the starter and generator, then you just need to change all of the light bulbs back to six volts and install a six volt battery (don't forget to repolarize the generator). If a 12 volt horn was installed, then you need to replace it with the correct six volt Klaxon 8-C horn. Also, you might have to either convert or reconnect your electric water temperature gauge (if the car still has the original electric gauge) so check that out too.

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