What is the best way to clean mold and rust from a car windshield?

JFF asked:


I just bought an '88 used car which has been sitting out in the sun for a few years. It has what looks like mold and rust on the sunroof windshield and I don't know what I can use to get it off. Any suggestions on a heavy duty windshield cleaner?

Mold Remediation Palm Beach County