Scott, I think you are talking about the outer edge of the fender lip. Correct? If so what my body man did was weld a round rod to the inside curl which makes the edge much stiffer. Then, so that no water or mud is allowed to sit in that area he used some bondo over the top of the rod and smoothed it to the inside of the fender. I know some people don't like to use bondo but it has worked for me for the last 10 years.
Hope this helps
George
