I just aquired a 1998 tracker and the gas gauge was showing full all the time . I checked the wiring to the top of the gas tank and discovered it was replaced with a used tank. the wires were cut and rejoined. Anyway,  There is a small wire tube containing two wires that both went to a ground . the YELLOW wire was twisted onto a screw and when I released the yellow from the ground the gas guage dropped to empty. Do ANYONE know where the yellow wire is supposed to go. 
TKS.   MOOSEHUNTER