I used goo gone and carefully used a ski wax scraper.....not recommended to do unless you are sure handed. .....and be prepared for a 1.5 to 2 hour job. Once I started I was like oh frack this is going to take forever, but I had no choice but to finish the job I started.
I contemplated ordering new visors in the hopes that they would come stickerless, but they are like $80 a piece.