No, it wasn't too hard. I located the studs and found a good spot in between and just measured for the hole really well to make the frame sit on the baseboard molding inside. The brick was cut with a masonry blade in a circular saw. A hammer took care of the rest. This one came with the sheet metal for the tunnel. I just had to cut it to the thickness of the wall. These type of frames are screwed to the tunnel instead of to the walls. We had some scrap carpet laying around from when the carpet was installed and I just used a spray-on contact cement to stick it to the tunnel. A little caulk around the frame and it looks great.