We recently added a bead detail surrounding some louvers on hood sides. Where this isn't normally the type of beads you see on running boards, it added quite a bit of rigidity & strength where something like this should correct the warp issue. You'd have to remove the braces underneath long enough to bead them, but a series of these added parallel would add quite a bit of strength.


http://www.garagejournal.com/forum/showpost.php?p=5865987&postcount=1982