Rolling tool cart trailer transport

JMO... but I wouldn't fix a tool box to a floor.
Having it bolted or permanently fixed/anchored to the floor will make the box flex so much that things will crack or loosen or break.

Best would be to put it up against the wall that has e-tracks and just strap it in. Let it move a bit and not fix it on a permanent place.

 

I had a HF cart like the one pictured in a trailer. Wanted to strap it low so I could still open the drawers without removing a strap. It was so top heavy I ended up adding a strap that went right below the lid. It would have collapsed at some point with just one strap.

 

may i ask why you didnt want to use ratchet straps?
i have a 27" box and roller. put d-rings on the wall (into studs). flat side of my roller is against the wall. the handle side of the roller faces out and has a ratchet strap on each side. never had an issue or needed to lock the wheels.

as long as you're using self tapping screws into studs on your trailer, walls will be fine.