It depends on the rabbit. They usually pick a spot to pee and/or poop, so you sometimes have to place the letterbox in the spot they choose. Some can be trained by placing their pee and poop in a box and they may start to use it. Mine never got the picture. Half of our hutches are wire floor, the other half is wood. Some of them decide to pee and poo in both places, so we put letterboxes in the spots they peed and pooped in, only when it was in the coop part. If its in the wire, we don't care because it falls down to the bottom of the cage. Once they pick a place to go, it can be very hard to make them go somewhere else. I don't know of any thread existing as of now.
