Did you get those case screws out yet? I did this before several times and got em out without drilling or damage. Take an old Craftsman 9mm 12 point 3/8 drive and a 5 pound hammer. Place the socket over the screw heads and forge it on with the hammer then simply remove with a 3/8 ratchet. You may have to do it a few times on stubborn ones. It's cheating but Honda did that to keep fiddler's like you and me out.