It is almost exactly like Kal's from The Electric Brewery.
Here is what I know so far. When I disconnect the signal wires from the shunt, everything turns on but I get a crazy reading on the meter. When I disconnect the signal wires from the harness but reattach the wires to the shunt, everything turns on, indicating to me there is not a short anywhere in the system and it must be the meter. And when I have only power running to the meter, I get a proper amp reading. As I flip switches, the reading goes up and as I shut them off, it goes back down. I haven't tested with a multimeter yet (it's late here) but from what I have read, the readings are in the range of normal. Now, where are the readings coming from?