This is something that worked out for me after a little effort. It doesn't look 100% correct, obviously, but we are quickly running out of options since no one reproduces these retainers yet and our cars are nearing 50 years of age. Someone may have a much better solution and, if so, I would love to hear about it. I started with the typical broken retainer. I ordered a Restoparts headlight switch nut (part #99L0109). These are metal and should be much stronger than the old plastic retainers. I gathered a step bit and two burrs (you might be able to use a Dremel tool or the equivalent) and used them in a cordless drill in order to better control the speed. I then used the step bit to drill out the hole for the headlight switch pull/push lever. This gets rid of the remaining threads attached to the retainer and allows the Restoparts threads to slip through the hole. I believe I only had to take it to 3/8". After enlarging the hole, I used the burrs to cut away the "shoulders" right above the lowest part of the retainer's face. The burr with the flat top worked well here because I could use the low part of the retainer as a ledge upon which to place the burr. I should have taped the "chrome" surface of the old retainer before beginning this process, as it probably would have prevented some additional scratches I made to the old piece. Once this is done, I had to do some cleanup to level and make my new hole as circular as possible. The idea is to come close to counter-sinking the Restoparts nut into the old retainer. Test fit a few times and cut as necessary to get the fit you desire. I wire brushed the head of the Restoparts nut before installation just to help it blend in better with the old retainer shell. Again, I know this will not pass a judge's show inspection, but it does help retain the factory look with a stronger part. Once you get it finished and start the nut into the headlight switch during installation, you can use a .50 cent piece or a wide, flat blade screwdriver to tighten. I hope this is of help to someone. It's a lot of trouble, but it is a remedy.
