It had to be done, I bought another keyboard. I now have a 2 manual stack that conforms to the AGO 2.5" and 4.25" keyboard spacing. Below is the new case for the great keyboard. I wanted both keyboard cheeks to be the same height. So I made them both 2.5" in order to get the correct vertical spacing. Unfortunately this meant that the ply boards that support the keybeds are no longer flush with the bottom of the cheeks.  If I did it again, I'd make the keybed supports from 10mm ply.

Another thing I'd do differently, the X-Keys. Not that they don't work well, as the do. It's just their dimensions make it quite difficult to incorporate without encroaching on the lower keyboard. Discrete piston switches are the way to go.
I have also invested in a 15" touch screen monitor.

Next jobs, finish the wiring, a coat of varnish and get a pedal board.