I used Adafruit NeoPixels to light up my R5-D4 eyes. The video shows a simple strand test. when I complete the Arduino sketch, I'll have different moods and events for the eyes (Happy, Sad, Surprised, Angry, Scanning, etc). I used Fusion 360 to design the mounts for the NeoPixels and got 6 and 10 mm glass cabochons from Amazon for the lenses. The main eyes each have a door peephole device. The dome is a Mr. Baddeley design.
Amazon Premium PLA PLA
I printed the eyes with the threads on top. I used the "cooling tower" to make sure the long eyestalk did not overheat and turn to goo doing the long vertical print.