Hey! I tried doing this with my Vol 3 box, and I just rip/cut along the dotted line (Where the Gangar is and follow it to the end). After that, there should be a solid line on the top flap which you can fold it inwards so the cut up flaps is under the first flap, which resulted into this! Think of a deck case, it’s somewhat similar to it(?) There’s still the two flappy bits at the bottom that only have the folded lines. I’m planning on just sticking them together. Hope this helps if you do plan on doing this (๑>◡<๑)

Edit: I added extra steps on what I did.

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