Last month I put 67 gauges in my 66 before the changeover my old gauge worked fine. When i plugged in the new gauge it immedeiately PEGGED out!!! Now when I plug in the old gauge it does the same thing only it peggs slowly compared to the new gauge that really jumps. I have tried reversing the wires only to have the gauge peg out on empty rather than full. I have traced the wireing and see no problems . any suggestions???