I did a light scrap but enuf to piss me off. I used a course piece of sand paper and kept reducing the grit. Final sanding was with a finishing sandpaper(wet paper)and kept spraying with water. It smoothened the bottom scrape substantially (took the rough edges off).I put a coating of tire/vinyl treatment on the chin afterward. Looks better.
I've scraped mine a few times...the first time within a week after I installed it. This is with 4X4 springs springs, so I can only imagine that you'd really have to be careful with lowering springs. Also, FWIW, this is why I can't see painting the chin. If your Stang is a daily driver, you will scrape it sooner or later.