Converting early ford gauges for 12V

I'm working on using '40 Merc gauges in my A with the 283 Chev engine. I know the speedo is a bolt on to my '40 Ford rear and I have the correct drive gears for the same.

Anybody know-

Can I just use the early Ford sender and a voltage drop, (Runtz), on the Fuel gauge? Can I use an early Ford Oil pressure sender and a voltage drop on the Oil gauge? Can I do the same on the Temp? How do I wire up the Ammeter, and will it work on 12V?

I only want them to work untill the fall when I will send them out to be rebuilt/refinished and recalibrated. I just want them to work for now so as to get some miles on the car while it's warm.

 

i have used several `40 ford gauge clusters with sbc's and i used the stock fuel, oil and temp gauges with runtz on the power to the gauges. use stock `40 ford senders and all worked fine.

double check to see if the `40 mercury actually has a amp gauge or is it really a volt gauge. if it is an amp gauge you should have no problem using as is , amp gauges do not care about volts. but if it is a volt gauge like a `40 ford.... do not use a runtz on it. a runtz regulates the voltage to a constant 6 volts , so you would not see any difference on the gauge between charge and not charging. i use a 60 ohms resister in the power for the volt gauge and then it works properly. when you turn the ignition on without the motor running the gauge goes to about 1/2 scale. after you start the motor and the alternator starts charging it moves up a bit more. this resister was told to me another here on the Hamb , maybe he will see this and jump in

 

Ford actually used 6 volt gauges well into the 60's with a voltage reducer in the gauge feed circuit.

 

I think I've got all the info to use these gauges from this thread and the tech archives. The worst I do is have to have one rebuilt which I'm going to do anyway. Decided on the Ron Francis solid state voltage source and origional senders. I'm going to see if I can get my SW fuel sender to work,( need to check Ohms), if not Macs has the right one.

Thanks guys.