So i found this Roush supercharger locally and i am wonder if it will work on my auto 2000 4.6L Mustang GT! I know the posting says it will, but i just want to double check with you guys

here is the link: http://columbus.craigslist.org/pts/829037710.html

also is that a decent supercharger? or are there better options for the price range (yes i have checked the sticky about buliding one but cant really find a head! and i dont have the $$$ to drop on a K/B)

thanks