First pass I tried to save room by soldering the power cord directly into the board. It turned out there was plenty of space on the back side of the board as seen below.
The boards are held in place with surplus proto-board. A slit has been cut in the corner of the the enclosure from the outside of the box to accept the holder. This keeps the board stable in both forward and backward directions.
Still missing the baffels, but the result is easily readable.