Flirc Raspberry Pi 3B and 4B Case Mount

These are case mounts for Canakit/Flirc Pi 3B+ and 4B aluminum cases.

I bought a Canakit 4B for my new CR30 and loved the case design:
https://smile.amazon.com/dp/B08QQ5KY1J

So I searched for the same thing for my existing 3B+ (on my CR10). Found both
3B+ and 4B models made by a company called Flirc:
https://smile.amazon.com/Flirc-Raspberry-Case-Gen2-Model/dp/B07349HT26
https://smile.amazon.com/Flirc-Raspberry-Pi-Case-Silver/dp/B07WG4DW52

For some reason the Flirc 3B+ case is a few thousandths of an inch deeper in the
Y dimension than the Canakit 4B case...

They are both "glove fits" to hold them in tight, you may need to do a wee bit of sanding
on the inside corners.

I had to add the top band for strength, kept as much surface area open as practical for
heat dissipation.