Chris, my apologies for giving wrong advice.
Took me a moment to realize you were talking about this portion:


Anyways, I'd imagine an easy fix would be to see if something like Chemical guys Back to Black would be able to mask it after every wash...

Otherwise, you may have to go to town with either one of these (which includes repainting the whole lower bumper with Bumper and Cladding Coat)

http://www.popularmechanics.com/cars...enance/2763656