I've just replaced the entire wiring harness on my 50 chevy, everything works except my fuel gauge and it was working including the fuel sending unit prior to replacing the harness. Here's my problem: When I turn the ignition key on, the fuel gauge needle moves up to the full position, yet my fuel tank is empty. I've removed the fuel gauge from the gauge housing and attached my two wires one is from the ingnition the other goes to the fuel sending unit and the needle stays on empty. When I mount it to the gauge housing the needle goes to full position. It almost like I got a short when the fuel gauge comes into contact with the housing but I never removed the gauge from it's housing prior to this and it worked. Should there be an insulator of some sort at the base in between the fuel gauge and the housing so they don't come in contact with each other? There was none present prior to removing it from the gauge housing. The other thing is that if I don't let the fuel gauge touch the housing the needle stays on empty eventhough I've moved my sending unit (float) manually (it's removed from the tank)up and down. There's no motion from the fuel gauge needle. I also tried putting my ohmmeter on the sending unit (which worked fine prior to the rewiring) to check for resistance should I not read something when I move the float up and down. Is there anyone out there that has an answer to this problem. I've spent five hours on this and lost for answers. This is a six volt system and I wire by ignition wire to the F side of the fuel gauge the other (E) goes to the sending unit.