Mine was the same as yours. My first sending unit worked fine outside the tank and no go when installed. After many times removing and installing, bought a new same style sending unit and it worked. Problem with the first was the the hot wire would lose continuity when installed to the center stud. I did run another ground to the cab brace, oringinal still in use also, can't have to many grounds. To correct my full to empty measurements, I bent the float arm a little. Not perfect, shows full, but still have several gallons left when empty. I like it that way.
