Jonnb, more than likely your carpet is glued down, if you plan on replacing the carpet just start ripping it out and throwing it in the can. But i have a good feeling your going to get into what i have just started. I had one soft spot so figured i would replace the soft spot and new carpet. Well, i pulled the carpet up and the whole floor looked like poo so i pulled the floor up and my foam is saturated and all of my cross stringers are pretty much gone. So now i am digging out foam and replacing stringers. This may not be your case buy if i were a betting man and you have the original 89 floor in there it's going to be the same.