383B Stroker Build
At the point in time where I replied, I guess I missed your intended power output. But, even still, I was only trying to demonstrate that with your intended RPM heads, and Jim's handiwork, your 496 should easily make your desired outcome since he's been known to make even more with iron heads.
In any case, I'm betting if you post up details of your build, we'll all happily watch :)