There are a handful of pictures floating around of tinted rear lights. I have seen both a lighter tint and blacked out.

As far as tinting your headlights, that's really not a good idea. I would go as far as to say it's plain silly. Why would you want to cut down on your nightime visibility, dulling the brightness of your headlights, by tinting your headlights? Even a little bit will have an effect. I don't think it will enhance the look of the X5 either.

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