So here was an interesting problem on my 73.
Headlights started winking about a week ago.....going up and down independently and NOT even shutting off. So I suspected after some searches on the good old forum here what the prob. might be. My first suspect was the light switch itself or headlight grounds. I had already replaced the all the relays in the car last summer so these I figured weren't suspect.......WRONG. After a sunny day yesterday and missing some of Daytona cause of major frustration testing the grounds, light switch sycronizing the lights ect. I took one of the relays out and noticed it came out of the socket pretty easily... WTF. So I measured the pins from an old OEM that I saved and measure the new one. almost .020 difference! I Carefully took a Starrett scale and stuck it in the slit in the pins to expand them.....stuck the realays back in .....that was freakin it!
Just can't underestimate the importance of the electrical contacts on these cars enough.