Welcome to the forum! I believe I had the same fireplace in mine. I've replaced it with a different model and changed the way it mounts but as I recall, the old fireplace facia came off with the removal of two screws on the right hand side by the manual control. Then, it was just held on with magnets and could be pulled off after sliding it upward about an inch. Once the facia is removed, four mounting screws are revealed and it pulls right out after they're removed.
Mine stopped working and I replaced it with a different brand when I replaced the TV with a 37" LCD. At that time I changed how the fireplace was mounted by building it out toward the room with two layers of 1x4 trim boards just to make sure the heat from it wasn't too much for the new tv above it. The new fireplace has a remote control which I really like. The fireplace isn't turned on in this photo but you can get the idea.
Rick, Nancy, Peanut & Lola our Westie Dogs & Bailey the Sheltie.
2007 Itasca Ellipse 40FD