MultiPi -- Raspberry Pi Cluster Case!

Update 2/9/2021 - I apparently made updates to this thing, which I never published. The updates are pretty significant, and the new version belongs on it's own Thingiverse page. As I'm somewhat lazy and lacking in free time, it may take a while to publish. That being said, you can access the Tinkercad files here:
https://www.tinkercad.com/things/jFNy7TUHkie

This is a Raspberry Pi Cluster case, which I've dubbed "MultiPi"
(Get it? Multiply? Hardee, har, har!)

1. Print the Upper and Lower, and put a RasPi in it!
2. Print the base for stability!
3. Print the Middle anytime you need to add another Pi!

This is still a thing in progress... Files may change!!

P.S. While you can technically stack 10, 20, or even 100 Raspberry
Pi's using this case, it's not really recommended due to instability issues.
You've been warned!

EDIT (5/27):
I've updated all .stl files. Here are the changes:
1. Flattened the top of the Upper and the bottom of the lower, mostly to