I am preparing to teach a seminar on how to assess harmonica customizing at the SPAH convention next week in Tulsa, Oklahoma. I designed and built a new light box for the event and I have already decided that it will be my main rig at my own work bench. This design is much simpler to build than my original design and is also easier to switch back and forth from backlighting reeds in slots to sighting reeds through the slots.
It is a 4″ x 9 1/2″ box on a platform that allows me to pick it up and swivel it around. The dimmable 60 watt LED bulb and dimmer switch are in the same box. I have a recess routed out to make it easy to use a wrench for centering when checking reed / slot fit. The knob on the side is an off on switch and you rotate it to dim or brighten the light.