QUOTE(Joe Owensby @ May 20 2012, 08:00 AM)
You have to make sure both the window and the metal piece are very clean in order to get proper adhesion. Make sure no old adhesive is on either piece before gluing back on. Maybe try a razor blade to scrape the areas and then clean with a cleaner.
...also a final clean with 70-90% rubbing alcohol or adhesive cleaner pads (like the Doctors' offices & hospitals use).
...and the OEM mirror tab is a few bucks (buy 2 - 1 for the next time), cut to proper base size (same for 911/912/930 & 914....others) & the current ones have used the improved 3M or Locktite type adhesive peel-off strips for a few decades now. Enough stick to stay on when surfaces are properly cleaned, but enough foam "peel-off" for NHTSA/US-DOT breakaway requirements in the case of a head hit during an accident.