Build a door frame rabbit hutch and jamb from 2-by-2 cedar; use 1-by-6 cedar for the door itself. The door and door jamb will need to cover the right half of the upper level. Since the upper and lower frames and the right leg form 3/4 of the door jamb, a 32-inch piece of 2-by-2 cedar is all that will need to be cut and installed about 16 inches from the right leg. Nails toenailed in on an angle through the piece and into the upper and lower frames should work well. Cut 2-by-2 cedar into 2 18-inch pieces and 2 30-inch pieces to make a door frame; nail framing pieces together at the corners.