67Dart273 said

Very good.
All you really need if you have a factory wiring harness is the wiring diagrams, to show the cluster connector and wire colors

This link, "71 Plymouth Chassis manual"

mymopar.com/downloads/servicemanuals/1971_Plymouth_Chassis_Service_Manual.zip

This gets a bit irritating because the scan of that particular book no longer uses original page numbers

The wiring diagram index is page 368 which is originally 8-147

Notice "instrument panel wiring" for standard and Rallye clusters so I'm guessing Valiant, page ---8- 160--161---. In the reader this is page no 381

Here is part of what you need:



This is looking at the connector on the PC board not the wire harness so you'll have to look at the REAR of the harness connector and watch wire colors

Example, find the temp gauge and the "S" terminal and follow that wire over. Notice it says "G2--18V" that is "circuit G2," it's a no 18 wire and VIOLET

I chopped off the diagram the fuel is DARK BLUE going off the bottom of the photo Follow the "S" terminal of the fuel gauge, it's G4--18DBL, meaning "Dark BLue"

Your oil sender wire is G6-18GY, meaning GreY. Now that is presently being used (non Rallye) for a warning LAMP but you can certainly re-purpose that wire for your new oil gauge wire

Click to expand...