Okay I removed my old rear mirror using a heat gun. Came off pretty easy. My new rear mirror came with the adhesive tape. I notice one side is a dark grey. Does it matter which side I stick on the windshield.

The reason I ask is because before removing my old one, I noticed it was white.

One side sticks to the mirror base, the other to the window. Doesn't matter...

They used to be all white. I'd imagine the new pad was made to be less intrusive meaning... Grey on the windshield side vs. a big white blotch.

Thanks all, looks like they did get smart and made a grey side, which will look alot better than that white shade that really stood out from the outside.

FYI, both side were actually grey in color. It was just the protective cover that was white. Any it is great finally have a clear new mirror.

when mine fell off, I used glue??

Since you have installed yours already this won't help you but may save someone a headache.
We had a rule in the shop I worked for and we had to use 2 people to install the mirrors. One would hold constant pressure on the outside of the windshield opposite of where the mirror went inside while the other would install the mirror.
There had been a couple instances in the past where someone pushed too hard installing the mirror and broke the windshield.

Just some thing to bear in mind.

Jim