Most standard nail-on 3/0, 4/0 and hanger boxes are called ceiling boxes. These boxes are commonly used for wall use. I couldn't find anything on the net that says they can be used in walls so I called the tech line on their web page. Dumb question right? Well they said they would call back with an answer but never did. Carlon plastic type L boxes (see link below)are stamped "for use in ceiling with non-metallic wiring systems only." These boxes would be perfect for wall use because the bracket is in the side back which allows them to be set out further for the thickness of stucco. The ears on standard 3/0 nail-ons are set too far forward so it's a problem if you have to set them behind shear panel. Got any input on this?

http://www.homedepot.com/catalog/productImages/300/b6/b636b22a-ab5e-4ed1-9eb9-92d77265149c_300.jpg