The best "tutorial" I have to show the process for forming multiple bends like that is this thread on a tailgate repair.... Where this is primarily flat and yours shows a bit of crown throughout the area, you could still make a hammerform that matches your cowl for a fairly accurate replacement.
Here's about 8 pages worth of reading....
http://www.trifive.com/forums/showthread.php?t=53428 Gumbi, Tell your uncle this isn't a T-bucket, repairing with steel is your best option. In all seriousness, fiberglass and steel have different expansion rates, so after a year or so of varying temperature changes, these forces will wreak havoc on the bond between the resins and the steel until such a repair delaminates.
If fabricating a repair panel using steel is indeed out of your scope, then I'd suggest finding someone else to do the fabrication/repair for you, or find a donor piece from a solid truck. IMO this would still be much cheaper than having to come back a couple/few years later and needing to fix it all over again due to delamination.
