For the main keyboard controller repurposed an existing midi piano keyboard and made some new housing for it that integrated a couple of LED panels, buttons and selection switches

the original keyboard

After cutting some of the unnecessary parts of the original plastic housing the first step was to model a close approximation:

And then some panel surrounding it and integrating a mount for led panel:

As usual we cut a cardboard mockup to see that everything looked good, the plan was to make a final version using walnut veneer plywood:

cardboard prototype assembled with tape.

Above the keyboard there are two Adafruit 16x32 RGB LED matrix panels

The spacing for the screws wasn't available online so me measured our own, here is an SVG of just the panel mount for reference: