Lots of wasted space due to extremely sloping roof lines. The first step was to reframe the opening to allow the bookcase to slide in. Although the wall is not load-bearing, I added a new header, king, and jack stud. I ripped down a 4'x8' sheet of mdf on my table saw and used wood glue and 2" finish nails for assembly. The bookcase is trimmed out in the same casing as all the doors throughout the house for consistency.