Restoring white headlight surrounds Options

[PancakePorsche]

I have typical cruddy, yellowed white headlight surrounds on my repainted car and I want to restore them the best I can.

Painting them would be easy and look o.k. but I know it is kinda frowned upon by the purest because it is not original and I agree.
Any known tricks out there ?

[scotty b]

SOooooo I've now tried Oxy clean and bleach ( independently ) in over night soaks, changing the hot water out every couple hours ( once it got cold again ) and a light scrubbing with a plastic bristle knuckle brush, and have not seen ANY change from the initial stripping. I've also sanded with 180 grit. This cleaned a lot of the "staining" up, but still not all gone. Next step is top try soda blasting, but I'm not sure these will ever be completely white again without paint

One of these was black paint directly on the plastic, the other was red oxide primer over spray. I have a couple more that had grey primer, grey primer + black paint etc. I'll try one of the grey primer ones next. Hopefully the staining won't be as bad as the black and red.

You'll see in one pic where I sanded a spot on each and how much of the discoloring that removed, hence my attempt to soda blast next. FWIw the sanding did not fuzz up the plastic, or leave overly harsh scratches. I think if I can find a way to sand off the staining, the housing can be progressively wet sanded back to a smooth OE finish