I think they may be different in terms of how the pipe connects from just ahead of the muffler. This point was brought up by Reagan when I was buying my Borla cat-back. They said that beginning somewhere in 2002-on, this connection changed from a flange to a "slip-joint" (I could be wrong about the name of the second one). So that would go to reason that a 2000 and 2003 would be different, at least in that respect. Hope this helps and that someone else can chime in.