I needed something pretty specific, so I made it!
it mounts 2 raspberry pi model 3s, as well as a uGreen SD card/cf reader, a 40mm fan, and a single panel-mount 30mm-spaced USB 3.0 header.
This is the SD card reader used here
I would recommend powering the Pi's over GPIO if you have a stable, safe current, but otherwise use the micro-usb power.
The V4 part screws in, and the SD card reader mounts with the SD cards pointing out and the cable coming out and towards the bottom of the drive bay.
The author marked this model as their own original creation.