Converting to negative ground is easy- - - -but it's a cop-out to keep from correcting the problem that exists, caused by the gauge manufacturer. If you decide to take the easy way out, simply reverse the primary wires at the coil, swapping the position of the wires from the ignition switch and the distributor with each other, switch the battery terminals, and repolarize the generator for negative ground. The starter, lights, and other gauges don't care what the polarity is. If the ammeter reads backwards after the polarity change, just swap the wires at the back of the gauge, but I don't think that will be necessary.
Jerry
