i agree on the flowmasters 40 series sound really good on the mustang. As far as installation just shop around and get quotes from several shops, everyone will be different. I had full exhaust done for 125$ (but i had already bought the mufflers before hand) Ebay is your friend, shop there for your mufflers.. also craigslist is good too. As for the suspension sounds like you need new struts and shocks.. might need new bushings too. Again shop around sometimes summit is cheaper and sometimes it's ebay. Just a little heads up.. Modding a car is addictive. I cant tell you how many times i've hurd someone say im just going to do a little and end up with every bolt on under the sun. As long as you enjoy it, thats all that matters.
If you would like the exhaust extra loud go for dumps.. just make sure they are angled to the side slightly so that it doesnt sound like a dump truck coming down the road.
