I've done it to my 300ce. Dude, I hate to burst your bubble, but this is not a fun project at all. It's extremely tedious, and it's not very fun to take the car apart and put it back together. But it does make a difference if you take out your seats and do the floors. The doors also make a difference. But expect to have to do some significant cleaning of the door panels since there will be 20 years of grease and dirt build-up.

I used second skin audio's damplifier pro. It's exactly the same as dynamat extreme, except considerably cheaper.

Good luck.