I'm thinking about picking up an exhaust system for my '94 Caprice wagon. I was looking at the Summit long-tube headers and Pypes Street Pro cat-back. I read in this thread that the cat-back's over the axle pipes would need to be modified to work with a wagon. How are the wagon pipes different and how do you modify an Impala/Caprice sedan cat-back to work? Is it just that the exhaust is longer or is there actually something different about the pipes as they pass over the axle?