If you are wanting to remain street legal you would need to keep the catalytic converter. That is if your state has emissions and vehicle inspections. The only way you could get away with running a straight pipe minus all the other equipment is to have the car as a track only car meaning that you can't register it to be driven on public roadways. But, if you really want to get the most bang for your buck and still remain legal, you can find a used SVT header, SVT catalytic converter and SVT flex pipe along with a 2.25" or larger exhaust. Then you would also need a tune to optimize everything as well. If you ask me, the Pacesetter header is a waste of money. It will rust to pieces before you know it.
But as I said, it depends on your state inspections as to what you can do. If you don't have emissions or vehicle inspections you can probably get away with running an SVT header with an off road pipe which essentially eliminates the catalytic converter.