How Many Voltage Reducers Do I Need?

I bought my Rebel Wire Kit recently and just wondering how many voltage reducers I need for my 46 DeSoto. What gauges would need them. I want to keep all the original gauges. I'm converting to 12v. This will be my first big step to getting my car on the road.

 

I know you will need one for the fuel guage so the 12volt doesn't fry it.

 

You will need one for each gauge that was 6 volts to begin with; the exception being the amp gauge which is as the gauge says, amps not volts. see <style></style>
http://www.jalopyjournal.com/forum/showthread.php?t=448038

Tom