A simple mount for adding low profile caster wheels to a Sidio Crate

I bought some of these Sidio Crates (https://sidiocrate.com) and love them for cleaning up my office. But once I stack them it's a bit hard to move the stack around easily.
I looked around to see if there was an easy way to add wheels to them and really didn't find an elegant solution. I toyed with making a dolly which would have been fine, however a bit too big for what I wanted.

I designed these corner mounts in Fusion 360 so that they hammer into the corners of the crates and then attach casters to the bottom.

These are the casters I used (https://www.amazon.com/dp/B07D7VGR1F?ref=ppx_yo2_dt_b_product_details&th=1)