Range Gear: Tuffy Security Drawer and What Fits In It

This question keeps on coming up, so there will be several occasional versions of this as I go along.
I used to keep three different range kits around, where I would have a sturdy bag set up with weapon specific accessories, ammo, magazines, etc.
I had a pistol kit, AR kit and precision kit. Depending on what I was going to shoot with, I would through an appropriate gun(s) and an appropriate gear kit into the car and head over to the range for some practice.
With this lockable Tuffy security gear, I basically have an "everything" kit. It is all there at hand, just add a gun and head on out.
https://tuffyproducts.com/products/toyota-cargo-area-security-drawer-toyota-2007-2014-fj-cruiser/