If you don't even have room for that, you'll have to exit the exhaust in front of the rear wheels. The Challenger T/A style tips have been over done IMO. If you could find(or make) a thin but wide rectangular tip for in front of the wheels that would look pretty cool. You can tuck them right up to the rocker pinch weld. I wouldn't dump it under the car. It will be super loud and you'll get a lot of resonance.