There is dedicated drill with the right angle for stainless steel, but you can use a standard one for a small hole. Lubricate your drill with an onion, it is not a joke, used on a former shipyard where I worked, and you will get round hole.
A friend of mine told me about the onion trick many years ago. When I was removing the baffles on my M3W exhaust I forgot about the "onion" and first used WD40 which worked but created a lot smoke. On the second baffle I remembered the "onion" and yes it works brilliantly with no smoke.
