hi spudgun. He you are retrofitting sidepipes then the only place to in is the factory. I've had it done to my s2. You will get a similar sound, but it could cost a bit extra he you want the sound of the gtn. The other option if all you are interested in is the sound is the factory or librands sports exhaust. Depending on your chassis serial number you get a twin or quad exit both sound great. See the exhaust sound thread to get some ideas.
