Has he tuned 2011+ 5.0's? How much would it cost me to go that route?You need a custom dyno tune in order to get it done right. The VMP tune does not take into consideration state of MA requirements.
Contact Pete @ Performance dyno, that's where 90% of us bring our cars. He'll get you tuned correctly and in position to pass and ready to go.
And again, would swapping the pulley and tune back to what I left the Roush factory with resolve this issue? That would be a lot easier, and cheaper, than driving all the way to northern Massachusetts from Attleboro for a new tune.