For my 2 Cents I'd add that a bit more research & thinking needs to be done. Don't know the exact situation in Il. on emissions inspection, but in most places anything modified beyond Air filter & Cat back exhaust won't pass unless you get a friendly examiner &/or have it set up so the computer thinks all is well.... Something for the OP to research a bit B4 making decisions, then plan how he wants to handle it!
How you deal with this issue is unfortunately the main factor in what "mods." you can afford to do these days engine wise, some members (depending on where they live) have to return the car to "stock" every year just for their sticker....