12 volt question and dust clouds

[GB SISSON]

I have done a few 12 volt conversions with chev one wires, but used aftermarket gauges. I would like to keep original gauges this time in my 47 truck. Is there one wire feeding the oil pressure, temp and fuel gauge that I put a resistor on or do I need 3 resistors for the 3 gauges? Also I only have napa here and I read somewhere they have the resistor or voltage reducer needed. Anyone have the part number? Thanks. Got the panel running strong, but want to have everything under the hood buttoned up before I install the front clip I picked up in Montana. Here's some pics my wife took today of the old man raging in the panel truck