Straightening Tailgate Sheetmetal

[Chad1376]

OK, Not really a paint question, but I figured this was the best place to post this.

The tailgate on my International is a single stamped sheet. In addition to the small dents and rust holes, the center "panel" bows out. This is like a subtle crease right along the bottom of the lettering. It's hard to see in the photo, but at the worst point, just below the first "N", it bows out about 1/4".

I'd really like to avoid trying to hammer this flat since my sheet metal skills are so-so, and I'm worried I'll just end up with a bunch of ugly hammer marks, or worse yet, accidentally whacking one of those nice crisp letters. I also want to avoid the need for high-build primer here since I don't want to muddy-up the lettering. I'll error on the side of leaving the crease to maintain the lettering, but if anyone has any suggestions, I'd love the hear them.

Thanks