David, I used 3/8th all thread and fasteners through super strut I picked up at home depot. The link below will show you what the strut looks like. All I did was cut the strut to lenght needed and used self tapping screws into the edge of the frame in the same place they mount the bottom panel.
Then used the all thread down through more strut. will try to take pictures when I can and post as its raining now.
http://www.grainger.com/Grainger/wwg...mId=1613555350