Ice Cube Tray Cover

I purchased a couple silicon ice trays for freezing broths and stocks. https://www.amazon.com/gp/product/B018G55I5C/ They didn't come with covers and when stacked if I wasn't careful to skew the top one it would nest into the bottom one spilling the not yet frozen cubes. I have a 3D printer, and as everyone knows the saying "If you have a hammer, everything is a nail", so I designed this simple cover to keep the two trays separated when in the freezer. I didn't want to insulate the lower ice cube tray so I printed with exposed infill. Any infill could probably be used, but I chose gyroid because I like the look. Because the cover is too large to fit my print bed, I cut it in two using circles to create locking tabs (a little fancier than dove-tails, but still quite simple to design). My cut is 0.1mm and worked on my well tuned Prusa i3 MK3S. The cut width is also parametric (see the sketch in the cut body to adjust the clearance.)

I created the model in FreeCAD v0.18 and provide the