Soren, the regulations used to be terrible. Sealed beam, low-watt lights and the dimmer switch operated by foot. I think even halogen sealed beams were illegal until the mid-1970s or so. The idea was apparently that brighter lights would blind oncoming drivers, and they probably would have with the terrible optics in those old lamps.

I don't really know what the current rules are (I know they've improved) because I live in an area where we don't have formal inspections for such things. I can do what I want, as long as no one complains.