Not sure what year Mustang you have, but I highly recommend Vortech. They make complete kits. Here are the links
1994-1998 V6 Vortech Kit:
http://www.vortechsuperchargers.com/...ustang_v6.html
1999 & Up V6 Vortech Kit:
http://www.vortechsuperchargers.com/...ustang_v6.html
I have been looking into a Vortech kit for my 2000 V6. You can buy it direct from Vortech for about $3600, but that was a little steep I thought, so I did some searching and found a company that sells the same kit for $2600-$2800 depending on the year. I have never puchased from them, so I can say how good they are to buy from, but for the savings it is worth a look. Here is their link:
http://www.sportcarmotion.com/vortech.htm
By the way, if you are real serious about buying one for your car, let me know, because I will be buying one for my car and perhaps we can put a group purchase together for AFM and save us all a few bucks. If you talk with them, let them know who sent you.
Also, there are a few Mods you should consider to make the most out of going with a supercharger. For one, if you are going to buy an exhaust system, instead of the common GT take off upgrade with the 2.25 dia pipes, you may want to consider an aftermarket system instead with the larger 2.50 diameter pipes. You will also want to consider a MAF and TB upgrade.
Then a new customer burnt "dyno tuned" chip for the car after you have installed the Mod's and Supercharger. The chip/dynotune could be worth 15-20hp out of the setup, not to mention setting up the fuel curves correctly to avoid detonation which can be hazardous to a supercharged engine. Besides, if you are going to get the maximum power from the supercharger, you will need to set the Rev limit higher then factory.
Finally, you will want to get some guages to help keep tabs on things like boost, temps, etc.
Keep me posted
