Modding the Beast

[MP99Alero]

Ok so, i found a few postings on this but i couldn't fine the answer i was looking for. I have the 99 4dr, with the 2.4. I'm looking to replace everything that has to do with the air flow. I already found the intake i want, and I figure I'll use the paceSetter cat back off of AAS.com, my question is, should i try to find something a little smaller than the 2.5in exhaust if I'm going to be sticking to the N/A theme?
I also wanna know of a good cat, I found a universal magnaflow, but is there something specific for our cars out there? I'm sry, to bother y'all with redundant questions. but thanks for the help I know you all will give me.

[[ion] C2]

booooooooooost

2.25 if you're N/A

[MP99Alero]

I don't wanna boost.......don't plan to at this point anyways, I've thought of going w/ a s/c later on down the road, but right now i want a fun, clean, quickish, ride that people won't expect

[[ion] C2]

CAI --> RSM 62mm TB --> manifold --> engine (P&P head would be nice) --> Pacesetter header --> 2.25" piping --> magnaflow high flow kitty --> 2.25" piping --> resonator --> some sort of muffler