I did basically the same thing. I just used common 2X4's for the end blocks with 1/4 in aluminum rods from the local hardware store for the rods. Just a 1X1/4 strip over the top of the rods screwed to the 2X4's to hold the rods in place. The critical parts is making sure the holes in the ribs are located very true, I used a jig in the drill press to drill the holes in the ribs to insure every rib had the holes in the exact same location. Works out very well.