Ford Repair: Fuel Gauge, ford bronco eddie bauer, eddie bauers

Question
I have a 1987 Ford Bronco Eddie Bauer Edition with the 5.0 EFI Engine.

Recently purchased and replaced the fuel sending unit going to my 33 gallon tank.

Upon completion, noted when filled tank that my gauge was up to 1/4 tank and this is without key turned on. When Key is turned, Tank peggs to empty. Drained tank during course of driving and when the tank was close to empty (I refilled with 29 Gallons at pump) gauge was registering just above quarter tank.

I unplugged my sending unit at tank and gauge jumps to full...

Being I have a brand new sending unit, I suspect ground problem or bad gauge. How would I troubleshoot this. I know I can short wires together, but do not know what wires will do what.

Would apprreciate any assistance you can provide...

Could this be related to the instrument gauge voltage regulator? Where in dash is this located?

Thanks for your time.  

Answer
The gauge is probably broke if you replaced the sending unit, and you would have to tear out the entire gauge cluster to replace a crappy factory gauge that you probably wont be able to find anywhere.  A junk yard will only sell you an entire new cluster, and its probably just as broke as the one you have.  Put a new gauge in, and run two new wires back to the tank.  Trucks are easy to wire, run it along the frame rail.  Use zip ties to hold it in place, and use good oil resistant wire thats not thin and weak.    Autometer makes several nice gauge pods that can go on your dash or A-Pillar, or just drill a 2 1/16 inch hole in your dash.  Make sure theres enough open space for the gauge behind where you drill the hole.  Do not go looking for wires that are frayed or broken.  If the wires were the problem, your gauge would never change position regardless if you took the sender out of the tank, filled the tank up, or smashed it with a hammer.  Ive never heard of an insturment gauge voltage regulator.  Eddie bauers came out in 1994.