Got a little more info for everyone. Borla has installed a muffler from their XR-1 line of mufflers. The muffler uses their patented multi-core technology and is specifically built for this application. Since this muffler is purpose built for the application, vehicle clearance is maintained. The muffler is not in the stock location, it is mounted forward of the rear axle and I'm told results in a 25% weight reduction from the stock exhaust system.
More info about the XR-1 muffler line here:
http://borla.com/products/xr-1_racing_exhaust.aspx
Here's a pic:
And another:
