Actually I read some instructions on how to do it, but I haven’t got around to it yet. Since I can’t find the link I’ll type them out as I remember them.
First of all you start moving the litter box over to the toilet from wherever in the house it is (hopefully its already in the bathroom). You move it just a little bit every day.
Then when you get to the toilet you start stacking up phone books or something day by day until the box is on the toilet.
When you get it up there, you cut a hole in the bottom of the box. Then I think you take out the litter.
After a while (maybe a few days until the cats used to it), you get rid of the box completely.