Modified Prophet 600 - Front Left Panel Detail

Here you can see that I used the membrane now only as artwork. I drilled through the membrane and the chassis control panel. I then rewired the entire matrix to the switches, and terminated that in a ribbon cable, with a connector. I replaced the membrane multipin connector on the left upper panel PCB with a mating connector for the ribbon cable. All the LED function was on the PCB, so that didn't require changes.

Done