AAHHH this is bloody awesome! I would really love to put this in the apartment. Only thing is it may get a bit expensive with the rack and electrical sets. Definitely something to look out for -- DIY mason jar chandelier
Light source above the cut out to project the shadow down. Could try and make the 3 in the cut out a bit shorter than usual, so the shadow cast is actually a perfectly formed 3, and not a stretched one.