1968 barracuda temp gauge and fuel level inop

Hi,

For a quick test disconnect the temperature sending unit wire and with the ignition switch in the run position you should see a pulsing voltage on a meter or test light between that wire and ground. If not the instrument regulator is likely bad. Also, a 27 ohm resistor from Radio Shack between that wire and ground should give a half scale reading on your temperature gauge. It's the same for the fuel gauge, that 27 ohm resistor should give a half scale reading.

Let us know what you find.