I just did this when i had my car retinted a few weeks ago. Isoprophyl (sp) Alcohol worked fine for me.I boughyt a bottle from Wal-Mart for 5 bux and i cleaned my rear and quarter windows in about an hour.
Agree with isoprophyl alcohol for removing most all glue from glass. Also the best for when you have to reattach a rear view mirror and get that glass super clean.