Ill try to help ya.
Alot of cold air intakes will work with the Saleen supercharger.
The problem is getting someone to make a tune for them.
Brenspeed can make you a tune for either a Steeda cold air intake or the Saleen Extreme intake. The SaleenExtreme intake is the better choice in my opinion as it comes with a better Mass air flow sensor and will support more power.
You do not need the reall big headers. Just get a set of 1 5/8 headers from any of the big name header makers. And get longtube headers. Kooks are real nice.
And no do not change your pulley without getting the car tuned. If you are still using the tune from Saleen you need to get a custom email tune or even better a dyno tune. Alot of people had their stock Saleen tune checked and found it to be lean. And if you goto a 3.4 puley you will need fuel system upgrades. Either a Boost a pump or even better a GT500 or Saleen twin pump system.
2005 Ford Mustang GT Torch Red Manual
Saleen Super Shaker 3.4 pulley/Brenspeed Tune
Kooks Longtubes Catted H/FRPP Stingers
Full BMR And Steeda Suspension
SOLD!! I have no Mustang at this time!