wasps, mice, and ?
Opcom: Mud daubers and wasps maybe. Looks like 2 kinds of nest? I can only say it's better than reaching into a long tektronix CRT box to pull the tube out and seeing a Brown Recluse staring back at me from the bottom. I let the spider keep the box.
Love the pictures of those tubes. I see you also are operating a 4-1000 amusement park ride there. There's a line.