Rear view mirror adhesive help please.

[greenhorn male]

I didn't want to use the permatex 2 part rear view mirror adhesive because it seemed a waste of money ($2.50-$3.50) using one drop and throwing it away and not being sure it would work. Specially when less expensive multi-use adhesives in larger containers claim good for use on metal or glass and could be used on other stuff as well. Well I should have listened to that nagging voice in my head instead of giving in and buying the only adhesive advertised for rear view mirror use. So I purchased the permatex mirror adhesive, cleaned the glass and removed any dirt and old adhesive with nail polish remover. Wiped it clean with alcohol and allowed to dry. Scraped the old adhesive from the metal mount, cleaned with nail polish remover and alcohol and dried. Followed instructions: applied activator on glass, waited 2 minutes until dry, placed a drop of adhesive on metal mount and stuck together. Instructions said it will set in 15 minutes. I gave it 3 days, put the mirror on and while tightening the mirror it fell off. Adhesive was obviously stuck on the metal but not on the glass. Glass was still wet from the adhesive. So, I figured I did something wrong and bought another package scraped the adhesive off the metal and cleaned everything like before only this time did it after dark, same instructions, but this time put tape over the mount and waited 20 hours. Put mirror on tightened hex nut and the whole thing fell of again
Ok done venting.... This time I asked for a refund at the parts store. Tell me, silicone adhesives or other multi use adhesives for use on both metal and glass would work. I used silcone to install my speakers in an oak veneer box for my home speakers and when I changed drivers one day it ripped the veneer off. I had to use a blade to cut the veneer around the speaker to save the box.

What have you used with success? I want the rear view mirror back on my burb.