Fusable lint too, my Coronet did that at a light, like someone flipped a on/off switch. I did the Ammeter bypass, Bat post on the alt to the batt post on the starter relay, hasnt happened again, most of the system voltage goes from the alt right to the battery.
Your lights wont dim or flicker any more when at a light with the turn signals, turn signals wont slow down when your at a light with your brakes on etc.
