yea but i went a way that allows for full bolt on, no cutting or altering of the stock M exhaust, its easier for me to play with an unaltered X-pipe rather than trying to fit a bunch of parts since i have no welder.
so far i have completly transformed the rear of the car, all fuel emissions have been relocated and centered just like the M and it has both heat sheilds and wheel whells just like the M, the body struts have been also swaped to accomidate the under body tray and rear difuser and the rear battery has also been relocated to proper M location.
i think their might be a new open market for stock M or even tuned M exhausts for people who want to do this convertion but its ruffly 90 percent bolt on.
i like being one of the few with a true dual exhaust NON-M z4's around.
ill post pics soon.