Finally laid out my old rear wiring beside my new M and H wiring and and found i had an extra wire thru the grommet and beside the fuel sending wire.I marked it,about 4 years ago when i took the cuda apart,as one end ground to the tank and the other thru that grommet and ground to a trunk brace.Im not sure if this is factory or not,but looks like it was added.Cant find any reference to it in the service manual either.Anyone have any thoughts?Is ther supposed to be a ground?