NES Case Slot

I built a Retro NES system a few years ago and wanted to have the cartridge slot usable to store the mini keyboard and battery that powers it. I finally got around to designing it and printing.
To mount, just use hot glue. the holes are there to allow the hot glue to mushroom up for additional grip and support.

My build can be seen here : https://imgur.com/a/KPi2n?gallery