So I'm building my first uds. I brought home the drum today and am ready to start the transformation. It came with a lid and ring. The lid doesn't have a bung hole or and holes for that matter. What is the best way to add a vent to the lid. I read somewhere that people drill numerous 1/2" holes equally spaced around the lid. Or would I be better of just drilling one large hole in the center of the lid. Any help is appreciated.