Similar to what Gord said, to me, knowing that the gauge is accurate when you get down to say 1/4 tank is most important. Thus I would empty the fuel tank completely. Then put in exactly 4 gallons which is 1/4 of a tank. Check the readings. If not directly at 1/4 tank, I would remove the sending unit and bend the pivoting arm accordingly.
Obviously you also need to make sure the float is not leaking.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear
My truck ....... Respect The Rust
If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
