Here's the link to the post I put on the Board after I replaced mine. There's a few of them on here, as many have done it in a variety of ways. It's not that difficult, and is well worth the effort in my opinion. For what it's worth, if you've got the fists and forearms of Popeye the Sailor, you'll have some skin in game, if you catch my meaning...
http://forums.pelicanparts.com/porsche-911-technical-forum/686604-installed-new-pp-sound-mat.html