Agree. Novus 3-part works well. But if it's really bad, I use a fiberglass cleaner (Gelgloss) first, then follow with Novus 3-2-1. Also works well on old turntable covers. A friend gave me an onld Thorens turntable that looked like he stored a cinder block on top (he blamed the kids!) Came out very nice, not new but close. Takes a lot of arm and a gentle touch.