I made something similar for Honey over 9 months ago. I didn't know this topic existed, so didn't do things exactly the same. The main thing I was aiming for [& achieved] was the complete elimination of litter. Anyone who has this system in place could do a simple modification & eliminate litter as well.
Just buy some fiberglass window screen replacement, cut it larger than the light grating & duct tape it around the edges to the backside of the grating.
Now the poops can be picked off the mesh. Then tip the litterbox & pour the urine into a clear jar with a lid & close the lid immediately. It can be emptied immediately, or if you want to check for sediment to catch a sludge problem asap, let it sit for awhile before emptying. Rinse out the litter box. Do this into another bottle if you're checking the sediment amount. Also add a little vinegar to the box to keep it fresher.
