One wire alternator problem

The wiring is totally factory. I have a friend suggesting that I leave the wire direct to the battery and connect the factory alternator to the alternator. I don't feel good about that. I've checked the wiring from the battery into the car, through the amp gauge back out the ballast. I haven't checked anything else. This was with the car not running. 12 volts at every source. Thanks 67Dart273