I've been looking into the same thing, mounting some extra lights mostly for seeing deer.
My friend mounted some pretty small LEDs on his jeep on either side of the wind shield. They are unbelievable for lighting up the side of the road including the barrow pit.
He said he doesn't think they are legal for on road use. But for where we live and drive in Wyoming it isn't really that big of deal. On our road, where my wife likes to hit deer, there aren't many cars in the daytime let alone at night. And the fuzz is hardly ever out there.
He turns them off, much like you would your brights, whenever he sees some other car's lights approaching.
