Is there any point in switching to an evo III manifold with a 14b? I currently have a 2g manifold (or what i think is a 2g manifold. The 14b is new, not ported. Would it be easy to port the exhaust side?

IMO, if you have a 2g already, and its not ported, port it out, and that should be sufficent for a 14b. If you actually have a 1g manifold, a ported 2g or EVOIII manifold/SBR manifold would be a nice upgrade for you.