I've got the exhaust mods with the K/N just like you, hopefully getting mine dyno'd the first week of april, let you know what I get. I'm expecting at least 296rwhp....but most of that probably because of the KN decal that came with the filter.
Edit - mine might make a little more because its O/R though.
A stock 2v with a paper filter will put down 211hp. Your stang will be around 225-230. My stang with the following mods on a dyno jet put down 244hp/286tq. Mods: JLT rai, Steeda T/A, Mac o/r H pipe, and 2 chambered flows.