I have relocated and installed a new gas tank under my rear bed of my 72 chevy truck, I cannot get my trucks original gauge to display the gas level. I connected the original fuel wire to the new tanks float sending unit wire and also grounded to the chassis the new floats ground wire but I still get no fuel display. Does anyone have any suggestion's on what might be happening. Please let me know. ps- I purchased a JAZ 22-gallon fuel cell tank w/float sending unit (tube type)
Might check what ohm the sending unit that you bought is correct. Correct me if I am wrong but I think you need 0-90 ohm.
Use an ohm meter to test the sending unit. If the gas guage work prior to the new install then the sending unit is a probable place to start.