On the front page of BonnevilleAmerica.com there is a "Downloads" link on the left. I believe they have an article you can download that guides you through the AI removal process.
I'm in the same boat as you - just recently bought an 05 America, and the stock pipes are just way too quiet. I'll be getting a set of Triumph Off-Road Shorts (TORS), as well as having the AI removed and carbs re-jetted.
Keep in mind that as you're in California the dealer may not be able to replace the stock pipes - mine wouldn't - due to new emissions standards that came into play as of 1 Jan 08. However, they were able to recommend a good independent "bikesmith" who's doing the whole thing for me for $200.
Someday, I hope to have the space/tools/know-how to make some of these mods myself...
-Dave
