Changed out my stock 49 woodie to 12v in 2006 and have had zero issues.
Get the 6v wiring harness and convert to 12 volts negative ground. An alternator that looks like a generator - Powermaster and EJ Whitney:
https://www.ejwhitneyco.com/automotive.html
12v to 6v solid state reducer - do not use resistors, wire this to 12v power and
the output to the 6V for your gauges:
https://www.ronfrancis.com/category/...rsion-products
Use a Bosch 12v blue coil for your ignition, it is internally regulated:
https://empius.com/products/empi-coi...illed-boxed-3/
I use a 12v AGM battery from NAPA.
Search this forum, there is a plethora of info on 12v conversions, about as popular
as what type of oil should I use.