Yea I was gonna say what Ian said. I had to do this on my trans drain plug.
EDIT- Is it totally round? Like a complete cirlce? Cause if you just rounded the edges off you might be able to get a smaller size socket on there or a standard size socket.
EDIT- Is it totally round? Like a complete cirlce? Cause if you just rounded the edges off you might be able to get a smaller size socket on there or a standard size socket.