I've been driving at night quite a bit since I've gotten my stang. One of the first things I got was the tinted headlight housing from American Muscle. It barely dimmed my headlights at all when I first installed it, so I know that isn't the reason. The headlight brightness has been gradually dwindling and I'm wondering what might be causing it. I installed a new HID conversion kit to fix the problem a few months back, but it didn't help at all...