To cut the opening in the face I used my Dremel Multi-Tool. Sadly my Fein was on the boat, but having back up tools is never a bad thing. In some instances I really prefer an oscillating tool for precision work, over a jig saw. In a situation like this my Bosch jig saws base plate would not have even fit on the face plate without wobbling. I also find I can do more accurate straight line cuts with an oscillating tool than I can with a jig saw.