I have a 1954 3600. Replaced the fuel gauge and sending unit in 2013 when I finished truck. Just last week replaced the sending unit again because the gauge was bouncing around especially below 1/2 tank. Then the gauge just dropped to empty with 7 or 8 gallons in the tank. I read about the importance of the gauge itself being grounded and I remember painting the housing. I removed the housing from the dash and I did not paint the inside of it. I took the gauge out of the housing put 12 volts to the positive terminal, grounded the sending terminal and grounded the metal strip between the 2 posts. The needle stayed on empty. If I removed the ground from the sending post and kept the ground on the metal strip between the posts it would peg the needle full. This just sounds like a bad shorted gauge to me. What are your thoughts.

Sharon