I need help. I'm trying to wire my electricial tachometer, but I don't have any idea which terminals to use for the wires. Also, my wiring diagram calls for three wires, white in from ignition, white out to coil, and green from fuse box; but I can only see two terminals, one spade type and one post with a nut. There are also two flush mounted screws adjacent to the spade terminal, but they don't seem to be for making wire connections but rather holding something internally in place.
Can any one guide me on this. This is the last thing I need to do to complete a total rewire.