I have a 95 Key West 1720 Sportsman CC. The fuel gauge goes all the way negative (to the left) when the ignition is turned on. I originally thought it was a wiring problem, but the wiring checks out. The boat has set for some time with fuel in it before I bought it, don't know how long.... It would appear the sending unit is defective, If I remove the ground wire, the gauge shows full when the ignition is turned on, but it doesn't seem to move. Any thoughts? The sending unit is replaceable, but I am reluctant to remove it without knowing what to replace it with.... Any suggestions as to where I can find the proper unit to replace it with?