Bad idea to have board sets on the side of the main cabinet. Who wants to be stooped over trying to get your meter leads to a test point to check voltages on the boards? Or worse, trying to read the markings on the board to see what the lit or unlit leds are for?
The boards should be all in the headbox where they belong, not buried down in the main cabinet. They could fabricate a swing out bracket for the monitor similar to a Williams insert panel.