Well, the electronics bit will probably be more or less the same as the mayhew-labs ledring. My idea is to have a ~270 degree arc, aprox. 5mm wide cut out in the panel, and then insert a piece of cnc-cut plexi. that will serve as "lightpipe" and diffusor (if wanted) Most helpful. I've realised that 16 leds obviously makes it impossible to have 9,12 and 3 o'clock positions. So either I skip one led or makes the arch having one extra led on one of the ends.