Phil,
Congradulations on your purchase; I love the 1989 Newell Classic. I had a 1987 Classic (blue, silver, w/medium blue accents) that I loved. If I could keep it a secret from my wife, I would buy another Classic. Boy, I loved that coach.
Anyway, the company that Newell uses is Peninsula Glass. If you send them your cracked windows they will replace the glass and you can have a local glass shop re-install them. I replaced one cracked, dual pane window in the bedroom of my 1993 for about $450 plus $100 shipping costs.
Penisula Glass Co.
6005 NE 121st Ave
Vancouver, WA
360 892-2029
www.rvwindows.com
Good Luck!