If you are not sure exactly what size/length of 80/20 to purchase I recommend going to a Pennsylvania company called Kodyn (
www.kodyn.com) who makes a version of aluminum extrusion EXACTLY like 80/20 but it is a much smaller operation. They also make fasteners that I believe are much better than the 80/20 counterparts. Dave, the owner, is willing to take drawings and even hand sketches and will let you know how much material you will need and will even precision cut it to length for you. Tell him Matt from Quasics sent you...