Sure, no rush. Those are even thicker, so that’s interesting!
These could be made much larger, since they aren’t meant to “snap” together.
Oh I wonder if that was the problem. Maybe I didn’t explain how to assemble well enough.
When you place the top of the case on, you should start with those two bottom tabs. Then it’s meant to close like a “clam shell” as you lower the top half. Those bottom tabs are meant to act more like hinges. If you tried to force the case down on those last, I could see them breaking because they’re so stiff.