Drilling and Tapping aluminum isn't overly difficult - just make sure you get the proper size drill bit for your tap. A mill would be awesome, but a drill press works too. Make sure your don't drill too far - and don't use power to cut threads! When tapping, just spin the chuck with your hand. If you can drill perfect holes, you can actually just use a hand-held tap.
(A punch, centering drill, drill bit and tap will probably cost you more than your light, btw.)
Practice on a thin piece of aluminum first, to get a feel for it and make sure everything fits correctly.