I've made mine in a 19' rackable 1U box (1' internal height) and I don't recommend it to you. The width is perfect but I've had to cut a large part of the folds of the top and bottom plates to let the stacked jacks, the LCD and the panel swithes fit in the box. This folds make the rigidity of the box and I've had to put 4 screws to get the rigidity back. I recommend you a 2U box (2' internal height) see this to have an idea of the final result:
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