Well if you plan on doing all of that to your sixer, then you're looking at a little more money than your average Joe. Like I said, be wise in this decision, if you decide to mod your six, be damn sure it's a car you plan on keeping, cause you will never get the money back out of it when trying to get a GT or Cobra. A ported split port intake swap with a mild cam would add a decent bit of power putting you near par with a stock 99-04 GT, however it isn't a cheap mod, and that's assuming you can install the stuff yourself. Engine work to me isn't hard, but for others it doesn't come so easy. Also, if you're going that far, why not get an M-112 adapter plate, and buy an M-112 supercharger and get even more power out of the car. I like twin screw designs much more than roots or centrifugal, however, for the price of the M-112 you can make modest boost with the thing and make the car much more fun to drive, cause I promise you, you will not be happy with the 200-220 or so rwhp you'll be making with just a ported split port swap w/mild cam. The M-112 boost 8 psi stock, and will add approx 10 rwhp per PSI so you'll be looking at somewhere between 270-300 rwhp with the M-112 on top of what I had spoke about (depends on port and cam choice). At that point you'll probably be relatively happy, however you'll need to upgrade your internals if you wish to run more boost to make more power. The M-112 will easily support up to 15lbs of boost, but after that I believe even that unit needs to be modified, which at that point I'd dump it and get a real supercharger like a Whipple or Kenne Bell.