When I was working on this renovation, the kitchen became bigger than the previous layout, so the cabinet was sized to the remainder of space. The TV was an existing 54" which was wall mounted on a coordinating cabinet panel. The bookcases surrounding the TV were designed allowing approximately two inches of space to the sides and top...but also considering the preferred height of the television for comfortable viewing ( sit on your sofa and find that tv height first). Allow for all speaker space and wiring the components before installing the Millwork. Hope this helps and let me know if I can assist with your project! Anne Boa