I probably should add this as well. You didn't say what your rear gears were in the initial post. Both of the engines you listed will be happiest with at least a 3.5 rear gear. More would be better. 3.73 or higher would be a good choice depending on tire diameter.

That's the problem with increasing cam duration. Contact ATK to find out what cruise RPM's at 60 MPH they recommend. I'm going to guess around 2500.