Playfield and metal cleaning products to use and avoid
Clean playfields and rubber with Novus #2 and polish metal with Novus #3; a hard paste or carnauba wax protects the playfield. Avoid Wildcat products and CP-100, which can yellow plastic ramps and lift mylar.
Systems
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part One, Clay Harrell (pinrepair.com)