Nereo, this one is easier than it looks. Google "Arlington vinyl siding mounting block". They make a receptacle box, with a mounting flange, and a vinyl siding trim ring. Grab one at Home Depot, mount the nailing flange to the face of the existing furring strip using a few short galvanized roofing nails, or screws, then add another furring strip to support the other side of the flange, and screw it down. Cut the siding about 1/4" bigger than the edge of the box and snap the trim ring on. That's it.