I don't know how far along you are in scraping the undercoating from your fenderwells, and how bad the integrity is of the undercoating. John Begian put me onto using Truck Bed Coating - I've used the Dupli-Color aerosol cans, available at any Napa, etc. store. The product name is TR250 Black Truck Bed Coating. It's easy to tape off the surfaces you don't want sprayed, and spray over the factory-applied wheel well undercoating. It retains the 'rough' factory spray-on finish, and looks great. You'll need at least a half-dozen spray cans, if going this route.
On January 12, 2017 at 9:54 PM "'Carlton Schroeder' schroe99@xxxxxxxxxxxx [Chrysler300]" <Chrysler300-noreply@xxxxxxxxxxxxxxx> wrote:
Hello from the very snowy and very cold Northwood’s of Wisconsin,
(and Eagle River, home of the World Championship Snowmobile Derby)
I am currently in the middle of the very unpleasant job of removing old and hard but very well attached old undercoating on my 300H. The bottom of the car is complete (sand blasted and painted although there was not much undercoating left) so it is only the inner and outer fenders (with thicker undercoating) that I need to clean of undercoating. The fellow who will be painting is reluctant to try to sand blast it off so I am using PB Blaster, Liquid Wrench, and kerosene to soften and then scrap off the undercoating. I’m working in about 50F temp in my garage so I could probably warm up (kerosene tube heater) the fenders further if that would help. Or if there are stronger solvents that don’t evaporate too quickly, that would probably help too.
I’ll appreciate all suggestions.