If you shorten up the rod it will be able to move in the tank better in both directions so that it will read full and empty I shortened mine to 8 1/4 inches but the way you do that is take the sender out of the tank and as your watching the fuel gauge lift the float until the gauge reads full if the float is above the top of the sender you will have to shorten the rod so the float is just below the top of the sender as it would be in the tank when you have a full tank than it should also read empty when you lower the float to the same depth of the tank if your tank is 18 inchs deep than when your float is at 18 inchs it should read empty check both ways before cutting your float rod I had to adjust my sender so it was 3/8s of an inch higher than the center of the tank.Now my gauge reads full and empty so i don't have to quess.

Pete

1952 Chevy 3100
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