Here's one I finished up and installed today. All made from scratch. Something like 22" x 30". Back is 1/4" black acrylic, dibond brushed aluminum as a backing. Everything is reverse engraved and color filled. The directory strips have steel shims on the back, and there's a sheet magnet on the back piece. Chrome standoffs hold a 1/4" piece of green edge acrylic.
Any feedback would be greatly appreciated. I did two of them, and this was the last one of the two.