Hi all. A detailer used some kind of thick black crap on my tires to make them shine. It was coming off all over the sides of the car so I cleaned as much of the stuff off of the tires as I could. But I noticed the other day that it's also all over the inside of the wheel wells. I can take my fingernail and scrape it off. Does anyone have a suggestion as to what to use to clean this up?