I have the MC in my '36 5 window. I cut an opening in the floor the size of the MC cap, then welded 3/4" angle iron around the opening and cut a piece of 1/2 plywood and laid inside the angle iron. The carpet padding is the same thickness as the angle iron, so you cut the padding to fit around the assembly and lay the carpet right over the top. A access hole can/will be cut in the carpet. I had floor mats made from the same carpet, so that covers everything. Rod