My 73 Z28 does not have the optional gauges but I have located a very nice set with a 150-mph speedo. I'll probably exchange the speedo with my original since the mileage is original. My question is about hooking up the AMPS gauge. This has a separate hook up not part of the rest. It has 2 leads as seen in photo 2. I need to know where to go with the wires I attach to them. Thanks, in advance.