I added it to my 365RD, had Curtis Carlson pull up the spec on the wall just to make sure nothing was in the way. Your right, I too was a bit nervous cutting through but everything went fine. I cut out the inside first just in case I messed something up knowing that the microwave would cover it. Drilled small holes in each corner, taped the fiberglass outside around the cut. Used an oscillating saw with fine teeth to cut it out.Have any of you out there added an outside vent to the microwave / cooktop? Should be simple if I had a template. Kinda scary cutting a hole in the side of the rig though.