Chev C60L fuel gauge

[Michael Eaton]

Hi, Anyone know the correct way to test a fuel gauge on the bench, my present gauge does not show fuel level in either tank. Also which side of the gauge should the positive wire from the amp meter be connected?I have tried open circuit to short circuit using a 6 volt power supply but only movement seems to be the needle moving from rest to the start of the markings i.e.indicating empty. Sourced a replacement gauge but this also does the same thing? Any advice appreciated. Mike