Actually, Shawn has the nice set up, especially since you guys run a lot at Laguna, er, Mazda Raceway 'cause his exhaust, which retains it's duelness, exits the port side of the car. I run a turbo muffler with, like, three inch ins and outs. The car is so quiet that it has been nicknamed The Stealt Car by those around me. However, because the exhaust exits on the starboard side of the car, it points right at the sound meter twix turns five and six at Laguna which forces me to short shift going up the hill which ain't no fun. That being said, if you can use the muffler and have it exit on the port side, well, now you've got something. To accomodate the big muffler, I raised the passenger floor about an inch and a half/two inches, maybe more, don't remember, if you need exact I can get that in a day or two. As the factory seat mounts are not used, heck, they don't even exist, putting in a passenger seat is no problem with the raised floor. When I get the new engine in, I'm going to retain the muffler position but try to have the exhaust exit in the fashion of Shawn. If you would like current pix, lemme know. Formerly Known As Elvis? That's just plain sad.