These little boxes perfectly fit the PLIs offered here. Which will light through some of the cards (barely). With a little sanding, bubble lenses will also fit on here. Though any cover - bubble or circuit card - needs to be glued down.
i love this because youre not constricted by a collar like its sister part. not only does it give you the flexibility of box location, but with a bit of hand work and a d-ring, you can make a nice approximation of the kobold d-ring.