Seen pictures that mirror what my tailgate had encountered, incidental damage to the thin upper edge, and the lower lip from being stood on.
I cut the upper lip off and am replacing it with 2-1/2" square tubing.
Should wind up looking stock profile-wise, with substantially stronger characteristics.
I may even make the hollow have removable end-caps so some chain or even a pry-bar can be stowed inside the cavity.
Here are some pictures of the surgical procedure;
I have gotten a little further than this on the profiling/cutting where the tubing will go, but need to wire brush a few hidden areas and rust convert prior to attaching the new tubing. Should get to it early next week.
More soon.