This is my first 3d model so it's a little rough.

The interior cell is 80mm x 34mm x 33mm Fits most Hotwheels. Some light sanding will be required for the joiner(idk what else to call it) to fit in the hole. Structurally it's pretty sound but when they're stacked on top they slide so if you want it permanent you'll want to glue them.

I ran it on PLA+ with 40% infill and at a speed of 20mm/s(probably go faster but it started stringing on me any higher)

I hope if you do make it you'll share photos and that you enjoy it.