My Dometic over the range microwave bit the dust on me. Out of warrenty and because of age the manufacture didn't make it anymore. Are you going to have your microwave repaired by a professional? I found replacement parts for mine but opted out of self repair when I read that the capacitor in it stores a very high charge for a long time and can send you into the spirit world. I had to make my own shelf for support and buy one that fit in the space of the old one. My original was mounted from the back with 2 very long bolts that went to the front. Look through the front trim on yours with a bright light to see if you can see the mount bolts. I did loose the vent option with the way I did it. Also my bet is you will need another person to help remove old one. It was a very tight fit. Hope this helps.