the best is to buy an OFF ROAD HID lamp with the ballast pack inside the lamp assembly. That way all you need to do is mount a battery , connec t the leads and switch. Brands like KC HILiTES, LIGHTFORCE, PIAA etc. Often you can buy a single lamp, for aorun $100 and up. They throw a light beam about 1 mile long if oyu get a spotlamp or about half a mile if you get a flood.