Here's a cheaper kit:
http://www.ftpp.net/V6Main.htm
Go there and click on the link "Exhaust" on the left menu. Then click the "Cat-Back Systems/ Rear Sections" link and then scroll down to the Mangnaflow. The 1st one it has listed at $365 is designed for the V8. If you wan't to buy that one, then you will have to have an exhaust shop fab up an s-pipe so it can connect to your cat, also that one is 3 inches, so the shop would have to weld in a size adapter as well so it can still hook up to your 2 1/2 exhaust. The second one listed at $402 is designed for your car and will bolt right up.