With my next drawer box build I will dado both sides, drawer and cabinet. No step in the drawer.
I forget some vehicles don't let water in them like the back of my truck does.
lol, you think you're giving commands to your pet? It's an inexpensive storage box, not a commuter highway bridge. Where's the sense of proportion?
I've been building with wood for over 30yrs, I'm familiar with the effects of water on particle board. If the cargo deck of my Suburban gets submerged I've got a lot bigger worries than a <$200 storage platform. And clear-coating sealants takes care of anything less.
https://www.flickr.com/photos/rayra/sets/72157647976429985/
well ... then you surely know particle board & melamine is not wood, and clear coat doesn't make screws hold any better or the material stronger.

Here's my setup and what's inside - ...
good looking kit
Thanks, I've been contemplating removing it. It likes to loosen up and rattle and squeak every few months, especially when it's cold. I may do a couple gear bags and only carry whats in the action packers while offroad. I haven't cracked them cases since I put them in a year ago...