If you want details about how to change the wires at the headlight switch to keep the headlights from popping up when the switch is pulled out to just the first notch, have a look at the thread excerpt below:
If, like me, you have an early car that pops up its headlights when the headlight switch is pulled out to the first notch, and have always wished it were not so, here's detail on how to do it. You need to pull the headlight switch out by dropping the fuse panel (make sure you disconnect the battery first) and then unscrewing the headlight switch knob and retaining nut. You can then pull the switch out from behind the dash and let it hang down by its own wires. It should then look like this:
Click to view attachmentThe three numbered light grey wires on terminal “K” are all power feeds for various things. #1 is the power source for the instrument bulbs, #2 is the wire that causes the headlights to pop up, and #3 feeds the optional fog lamp circuit. You can distinguish #2 from #1 and #3 by the diameter of the wire, #1 and #3 being slightly larger than #2. To correct the behavior of the pop-ups, we want to remove wire #2 from terminal “K” and hook it instead to terminal “51” on the opposite side at the front of the switch. Cut wire #2 as close as possible to the connector and crimp on a new female tab connector.
Since there are already connections to terminal “51”, the easiest thing to do is use a “piggy-back” connector which provides a second male tab for the wire already on the terminal. If you can find them, there are crimp-on terminals with this feature, but there are also separate piggy-back adaptors, which is what I’ve used here.
Click to view attachmentAnd, since these are hot terminals, I always like to insulate the exposed metal with heat-shrink tubing.
Click to view attachmentHope this helps.