X2! If you have a wiring diagram find what wire it is and what it does. The gauge and low fuel light get a (ground) signal that's how it knows what the level is. Your problem may not be in the tank but a short somewhere else.

 

Makes ya wonder, don't it?

May want to verify the fuse for the pump is the correct size.

 

The fuse appears fine, the crappy Chiltons book I have shows only the fuel gauge and low fuel warning light run off that wire. I haven't had time to drop the tank and get the whole thing out yet, that'll be on my next weekend off.

 

Finally got time to finish this off! Turns out that the wiring rubbed through the loom and two wires in behind the gas tank, fusing all the wires in the harness together from the front all the way back nearly to where the rear ABS sensor wires split off! I ended up getting a whole harness from a wrecker and replaced it today. Though they cut it just after the ABS split, so I got to spend more time cramped under the truck wiring in tail lights. The old harness was a bit different, it had factory trailer light wiring and the new one didn't, but I don't tow anything so I'm not worried about it. I tried to get the tank as empty as possible, turns out it was right on empty! I dumped in gas a bit at a time and the gauge seems to work properly now. Now onto other issues...