Blank face plates on a shelf, and the cable boxes sitting backwards on the shelf so you can mount the emitters on the lacing bars. One box at the top of the rack, one in the middle, and one at the bottom so you don't get any cross talk could work.

Then again, maybe a 4" to 5" tube, like a toilet paper roll core, taped to each individual box and the emitters taped to the tube?


I tried the pinhole thing and had no love.