I have to give credit to HiHoAgRV for this one... I struggled with how to rebuild the bent up, broken, and reriveted curves of C-channel. I talked to a few sheet metal workers, and they simply said no way. Another company quoted me $800 for the four corners bent from extruded channel. To put it simple, there is no easy way to "bend" a channel without breaking it. Then I ran across his post and it made perfect sense. I had two pieces of angle bent out of .0500 aluminum so it has some strength, cut it on 2" increments for the inside curve and notched the outside curve so it could flex in without overlapping. Then I flipped my old existing channel upside down, copied the width at the middle with the two angles, cleco'd it fast, and simply worked the curve one section at a time. After all of the holes where drilled, I removed all the Clecos, removed all the burrs from the new channel, reinserted the Clecos from the bottom of the new curve and riveted it fast... It took a bit of time, but well worth it!