I didnt Glue I used a bunch of Rivi Nuts in to the back wall. Logic tells me Glueing would be better but dont think glue will stick to foil on deaner, If your going to glue it I would pull off deadner and clean up with acetone and scuff up paint with 60 grit grind wheel and glue- it wont ever come off lol but i like to do things that can be undone or repaired easily and glue isnt one of those things lol . I will try it out like this first and see, Its gotta be better ! crap it was flexing so bad I thought I was going to lose my back window.