Hey about sound dampening....
Go to Lowes and buy what they call "Peel-n-Stick" adhesive asphalt lining. It's the same stuff that Dynamat is made out of... $0.99/sqft. You dope the whole car twice for $50. Lots of discussion on this at
www.diyaudio.com under car audio section.
If you think that's too cheap, Check out
www.b-quiet.com. They are bit more expensive than Lowes, but still gobbles cheaper than others.