need some advice...70 Duster hood

i removed all the factory dampening material from between the hood skin and the hood bracing because some of it was missing and some of it was brittle. It is now time to re-apply the dampening material, any advice on how to do this, I am afraid i will create high and low spots on the hood if im not careful. Is there a way to have the skin relax or be in a neutral position? not sure that makes sense.. any advice is welcome,...thanks Rich