I would think if you are swapping the same engine for the same car, it should be just a mechanical swap.
Example: If you're swapping a 3.2 normally aspirated engine from a Limited, SE or Base and you use all of your electrical connections, it should be plug and play. In my opinion.
I've done engine swaps before, but they were on older muscle cars and pickups. I haven't done any on a Crossfire.