Afterward, use something like Mequiar's #40 or Meguiar's Gold Class Trim Detailer on it, let it soak for at least fifteen minutes, and then buff it off. Apply a second application, wait another fifteen minutes, and then buff off any excess. I found on my wife's Escape that if I do this every two weeks, tar does stick as bad. Don't get me wrong - the tar still gets on there, but it's doesn't seem to be as big a pain to get it off after treating the cladding like I described.
