stock87...first off make sure the bulb is working <img src="/forums/images/graemlins/rolleyes.gif" alt="" />... then if you look on top of the fuel tank where the sending unit mounts you'll see a connector, 4 wires on the harness side and 2 wires from the sending unit... on the SR5 sending unit there are 4 wires... so if you got 4 wire plug going into a 2wire sending unit then you'll need to install the SR5 sending unit in the fuel tank... the STD unit doesn't have the low level sender... so obtain the SR5 unit for your year and you'll be in business.