I used super 90 or whatever to glue it on... basically just gave a quick wipe on the existing dampening sprayed the glue on both surfaces.... let it dry for a min, then slap i on... I also used open cell foam on the inner door cavity. Actually made quite an improvement IMHO.

Im not too worried about this stuf going moldy , its closed cell foam so its impervious to water. and i dont believe TOO MUCH water goes into the doors anyway. (exept when washing the car)

I still have lots of foam left, i might do my passenger doors with it and the wheel wells to help quiet the whole car.

 

On the same topic of deadening etc...I checked out the 2 loud 4 u website...and found they carry a different type of deadener material...called Magic Mate-400...apparatly, when the material is heated it hardens to somthing comparble to concrete!...I plan on buying a bunch of this stuff n to deaden my entire trunk with it...this should turn my trunk into a solid enclosure...with the need to use messy fibreglass or even extra MDF...this stuff is used for SPL competition vehicles in Europe.