Originally Posted by Emilgevor
I have cleaned several different housings and I can tell you my results. first time i tried swirling a cleaner around inside the housing. It cleaned the inside surface of the housing but it also removed some of the reflective "chrome" plating on the plastic parts. If you go this route be sure to tip the housing down and only swirl the cleaner on the clear plastic.
The next time I tried a different approach. I remove all of the components from the housing (low beam projector, high beam bulb) and used a small dowel rod with a wet microfiber cloth to wipe down the inside of the clear cover. This worked a bit better as I didn't remove any of the "chrome" plating. I spent about an hour on each assembly and they cleaned up pretty good.