All of the parts I used to order my light stand were sourced from www.8020.net. Below you can see the parts list I ordered when I made my light, I kept the long piece at 48" to keep the shipping prices down. The 11" piece is the lenght I needed to get the light bar over the center of my tank. Keep in mind that you may need to add lenght depending on how you mount the framing together. Using the 11" piece it was actually 10" since I mounted it on top of the 48" piece. Next is th 14" piece, this is the piece that spans left to right over the tank.
I used the 4 hole gusseted inside center corner bracket on the 48" and 11" piece. Which is complete overkill for hanging lights! The 2 hole lite inside corner bracket was used to mount the 14" piece to span the tank. Next up I used the 4 hole wide inside corner bracket to attach the 8020 to the 1x6 I used to extend the light fixture and reduce shipping costs.
In the video below I explain more in detail the light mount I am using.