Theres actually special glue made by certain companies made for this exact purpose.
I dont know who makes it, I wish I could be more helpful, but I remember reading on the back of a super glue bottle that its not meant for this exact purpose. Its too stiff, it doesnt flex at all. I
best bet is to use rear view mirror glue, you can find it at any auto parts store, other stuff like Gorilla Glue is going to fall off faster. I used to lose my mirror in my Blazer every time I used to crank it up.
can always have one ran from the roof like a lot of car makers are doing now for the reason of them falling off down here in the south with the heat melting the glue up... just 4-6 lil tak welds and good to go
I've had best results with the permatex kit. This last time it's held since summer, before that it broke every month. It's only like 1.50 a package at walmart so I stocked up. It's been fine for a while though. Once I throw in the 18w6's it'll likely break again so i'll just leave it off.