I painted mine with all-purpose flat black spray. Name brand, but nothing special. It's holding up fine, looks exactly the same as the day that I painted them. I've got stock bulbs.
I seem to remember some warnings about hi-temp paint. I'd do some searching on the site and see what you come up with.
If you're careful, and do a good job, your headlights will look awesome. Just don't paint over all the silver. If you paint too much of the housing, it will look weird.
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