So I was driving on the highway and saw a black item just bounce towards me. I knew it was something that would do damage so once I saw it bounce in the air, I sped forward because it was heading for the hood. Luckily I saw it go above my car and I thought, "F-yea, dodged that shieeeet." But a split second later I heard a big, "Thump" like something dropped on my car. After getting to my destiation, got out of the car and saw no dents but a scratch on the roof-top. I put touch up paint on top and now I'm wanting to sandpaper it smooth. Which type of sandpaper grit should I use?
Thank you..