My 1982 Datsun 720 Pickup has an issue with the headlights. Seems as the colder the temperature is out side, the longer the delay is between flicking my low to highbeams off.
Regardless if I turn on the lights with the high beams OFF, the lights automatically start with the high beams ON. Can take up to 5 minutes to dim when real cold, and can be as little as 3 seconds when its warm outside. Pretty sure its either the Headlight Relay or some sort of fuse. Replaced all Headlights and the relay once, But the relay i bought was not the same one that was in the truck when i replaced it. Not super car savy but even my dad didnt know exactly why is could be doing this. Any help is appreciated. thanks!

I have a 720 with the same issue, I believe it is the relay.

You probably have the issue taken care of but if the relay is old and cracked moisture can get inside of it and the cold temperatures can freeze it until the relay warms up. I'm having an issue where the head lights will come on and the dash lights are delayed. Doesn't always happen but it is odd to see when it does