This may be a dumb question, but here goes.
Looking at the Borla web site they list no exhaust for the '03 Xterra.
They do list part #14873 cat back exhaust for the '00-'02 Xterra.

Is there some difference big or small which might make this not fit the '03-'04 models?
I know the Gibson cat back states for '00-'03 models.

I would like to know before I go spending hundreds of dollars only to figure out it won't fit due to some silly bracket or something.