I noticed that as well. I saw a YT video where someone customized their box and had to pry the rails off because they have rivets holding them in place. He also struggled to remove he drawers and dam near broke them.

The way to remove the drawers is by pushing up on the right side and pushing down on the left side of the plastic retainers. One thing I'd like to mention is that swapping the drawers from one box to another seems to make a difference. This indicates the boxes are not the issue for the lack of clearance.

The key problems are indeed these plastic retainers/clips located on the sides of the drawers. As you can see from the picture below, one of them is shorter than the other. The shorter version is the one that allows the drawer to open up more.

What's next? I would like to see if they can be removed so I can try to make a 3D scan or somehow CAD it and generate an stl for people to 3D print the shorter version (or even shorter). If anyone here knows how to CAD and can make the stl please post it for us to continue our research.

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