oh and i forgot to add, with a dremmel and the right wheel attachment (not just a grinding stone) one could probably gently round the sheet metal inward so that the finished product is smoother and looks like it came that way.
you could probably use a bolt with a domed head that has no slot in order to get those screws looking smoother. they have them where theres a square protrusion just above the threads to keep them from rotating, kinda like a small carriage bolt?