I liked https://www.printables.com/model/534188-kobalt-mini-toolbox-inserts/ but the base for it used Clickfinity and I thought Gridfinity itself was fine. Threw together this base-plate from https://www.printables.com/model/377158-parametric-gridfinity-base-plate-freecad-file-incl that should fit the drawers of the toolbox.
Top and top drawer allow for 3u height modules. Bottom drawer allows for 6u
Update I added a grid for the top section as well. Supports two 20x6x2 magnets to hold the top better.
The author marked this model as their own original creation.