I was on my way to Gwinnett a few weeks ago in my 79, and my ALT light kept coming on. I went home and it was staying on at that point. I looked at the belt and it was as tight as it should be and looked at the plug into the ALT. It was plugged in. Then I noticed another wire coming off the ALT just to the side of the plug. It was just hanging there just near another plug in. I plugged it in and the ALT light immediately went off and hasn't come back on. Just check to make sure no wire came loose from the ALT??

Later, QD.