I'm in the process of designing a new coop for 4 hens. The coop will be 5'x3' and I need to have external nest boxes. However, the boxes would have to be attached to the door I need to open to clean the coop (a 2'6" door). So, has anyone ever built external nest boxes that could be removed? The only thing I would need to get into the coop for would be to clean it.I don't need it to be waterproof, they will be in the run with a roof.