[Caddylackn]

What are your skills? Can you weld?

What are your goals? Does this fix have to be perfect? Is this a show truck or a driver?
What is the final color?

If you require this fix to be invisible, and the final color would be very dark and shiny, I feel that this upper section would have to be cut off and replaced with original sheet metal.

If it doesn't have to be perfect, I think you could get it close by pulling it and hammer massaging it back into shape, then bondo the imperfections. It would be hard to get this area bondo'ed and sanded and look perfect since there are many compound curves. If the truck was white, light green, silver, or yellow this repair would be hard to pick up. If it was black, or dark colors any slightly flat spot in the rounded edge would be visible.