I have used alcohol and magic eraser on all the machines I have restored in the past, It really works well and gets the playfields to look so much better. You do have to be extra careful and work in small sections slowly to avoid removing any of the playfield paint. Thanks for posting.
Will this also work on cabinets? Currently working on a Capcom Breakshot and both the cabinet and playfield have really stubborn spots. Unfortunately on the playfield most of the bottom half has mylar so I'm not sure if I can clean those areas.