Exhaust Question
If you plan to drive the car anymore than 30 minutes at a time do yourself a favor and run the exhaust to the back bumper. Dumping at the wheels just makes the bottom of the car a sounding board for resonances and will result in the interior being very uncomfortable for long drives, especially if you are going to use the super 44 mufflers.
Also, I believe Flowmaster has minimum recomendations for pipe length after the muffler in order for them to scavenge properly.