Oh I like that! I have yellow plastic trays I use to hatch in for the same reason, and when I overflow them I put the eggs in the bottom half of egg cartons. I don't know if 3 days or 5 makes a difference, but after 5 days most air cells have settled. The other thing I've read is not to move them on day 4, there is something about the development process on that particular day that makes them more sensitive to handling.
It's all put together now we just need to install it in the coop and test it to make sure things are working as they should. The spool is off the drill because I need to glue it in. The green is tape to cover the wires. I should've cut them so they weren't all over the place, but I was too lazy at this point. The plastic container in the middle of all the tape holds the electronic components. I can't wait for this to be working!