I have had a good search around and beyond quite few people reporting problems are there any particular tricks to removing the headlight stalk and giving it a complete overhaul?
The issue is the one that others have encountered which is the lights turning on by themselves presumably due to dirty worn internals which allow the contacts to make when they shouldn't.
I have pulled the steering wheel and the covers but the Headlight stalk seem to be riveted ?
The switch is riveted together, so you would have to remove the complete switch from the column and take it to your workbench, then drill out the rivets, to carefully take it apart. If you wish to do this, make sure you have some small screws and nuts first, so that you can bolt it back together afterwards. Also I suggest doing this work on top of a light coloured towel (I use an old light grey towel) and be very slow and careful as you dismantle it so you can see how it all fits together. The towel is there so that anything that falls out, is retained and does not roll or bounce away and become difficult to find! These switches are not meant to be taken apart, but I did mine many years ago (in fact probably 38 years now!) and it has been fine all the time since then. The fault wasn't worn or dirty parts, since mine was less than two years old and the fault had been intermittent almost from the start, so the parts had not had time to wear or get dirty. No, the fault was the internal contacts are small and very close together, and had probably been bent very slightly by poor fitting, and the contacts had become close enough to be almost touching, and certainly close enough for a circuit to be made by the potential jumping across the tiny gap, or even leaking across the lubricating grease because of condensation maybe?
Once I has corrected and refitted all the parts and screwed the casing back together, it worked and has remained free from faults since.
If you don't wish to attempt this tricky job, the switch assembly is exactly the same as fitted to some Horizon and Tagora models, and maybe the Alpine/Solara although as I've never stripped one of those I can't confirm that. So if you can find one of those, it would be a straight swap.
Roy