I replaced our microwave yesterday on our Catalina 350, the factory installs would probably be similar. As stated, above remove the side panels and then look for screws driven in from the bottom into another piece of plywood. I would assume the same process would make sense to both manufactures, basically, the oven gets attached to another piece of plywood and then that's gets screwed down. From there reinstall the new oven the same way, mine was screwed down to the second piece of plywood with small "L" brackets. It took some looking to find another oven that would fit measure all 3 dimensions. I wanted to increase the size but found that on our install a "dorm room size" .9 cubic feet was the only option as all three dimensions are critical. Obviously the install needs to be rock solid so follow the factory install method. PM if you need photos. Also, I have about 3" of space on both sides of the oven that is "dead space" You may want to recover that extra storage by reengineering the side panels to allow access to each side by cutting to the proper width and then modify the height to allow access to the "new" storage area. Mine need to be trimmed by about 1/2" each on width.