Classic/Antique Car Repair: Ground Wire (Gas Tank Sending Unit), gas tank sending unit, fuel gauge

Question
Hello Mr Benjamin, I'm in the process of having a 1966 GTO restored.  We are not quite sure as to where the ground wire from the gas tank sending unit attaches to. If you could help me with this question, it would be greatly appreciated.  Thanks so much, Brenda from Michigan

Answer
I don't know exactly where the factory grounded this wire, but it really doesn't matter in the function of the fuel gauge. Most probably, it went to a tapped hole in the chassis rail somewhere - if you have the original sender ground wire, you can use the length of the wire to estimate about where you might find the tapped hole.   All that matters to make the gauge work correctly is that the wire be grounded to a known good ground - and the chassis metal is always the best place to find a reliable ground point.  There must be clean bright metal (no paint or other insulating medium like undercoat) can be between the copper of the wire and the chassis, else the ground will not be electrically sound.

Dick