Would an 05 ap work for an 04 wrx also?? has anyone tried this. tried the search but nothing definitave.

Yep it will Visist www.wrxforum.com (cobb forums) and find the update to make it work with 04.

04 & 05 WRX AP are interchangeable with updates from cobb.

awsome, I jsut checked cobbs website and they have the update, that is awsome, I had called Cobb erlier and asked and they were like yeah, it won't work, you'll have to send it into us and it costs like 400 or so. I was like hrmmm, let me ask around