I have no idea how to hook up a factory temp gauge and voltage gauge in my 68 gmc.. When I got the truck it never was hooked up and I need to find a way to get them back up and running again..
Thanks, Stephen

You ammeter wires are shown with a four amp fuse. 18GA B/W and 18Ga B in the diagram. The temp GA wire is the 20GA D/G wire shown above the alternator in the drawing. If your wires and guage are good it will move all the way to the hot side if you ground the dark green wire. Also check the wire for shorts sometimes the get burned on manifold. The ammeter fuses located by the batt junction block on pass side fender and around headlight on drivers side. Heres a diagram.

Thank you very much bud.. I have been needing to get them up and running for a long time now.. I couldn't find anything on the web so I thought someone here might have some info.. Thanks, Stephen

Keep in mine that the PO might have changed the dash to gauges and did not change the wiring harness. That may be why they were never hooked up.

Go to the sticky thread on the top of the electrical forums and scroll down to farside's thread and you will get some great schematics to help you. Yopu asked about a voltage gauge but I assume you meant an ammeter. They are different animals. The picture below is a very basic
schematic of the installation.

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