i had a problem with my fuel gauge as well tested all the wires volt regulator and grounds so that left me with the sending unit. i pulled it out to find that A the filter on the end had degenerated and fallen off and B the brass float had worn a hole in it from where it rubbed on the bottom of the tank. i hooked the unit up and moved to float arm to make sure it worked. finding that it did i didnt have to buy a new one and they are pricey. i cleaned it up with carb cleaner and wire brush put on a new float and added an inline filter outside of the tank along the frame. that was my fix, and advice lol.
