I replaced my underdash wire harness on my 66 GT. Everything is working, yeah! But, ever since I replaced the wiring my amp meter will bounce when I turn the turn signal on. The needle will sit at the half way point or just about the mid line on the charge side. But when I turn the signal on it will bounce down to half way between the mid point and drain side. It bounces along with the signal. Turn the signal off snd it goes back to the mid way point between the C and D and stays there. Any one know what's happening. I don't remember it doing this before I replaced the harness.