You can get the mil eliminators or you can get an X-pipe w/cats. You don't need a lot done to your car before a chip, but you should be a little further down the road than stock. My chip makes a difference, but if I change too much (which is likely cause I'm close to stock too) the chip has to be changed again, and there goes another $400!
I think if I did it again I'd go with cats. AB has no emissions testing, but when you go to places like say
Dallas, you're screwed.
------------------
1995 Mustang GT