car title swap/across state lines

Sounds about right to me. Be careful with Louisiana though they are going to probably try to tack on sales tax once you try to register it here (even if you paid nothing for it). I would see about registering it in NC or your BnL letting keep the plates for a while to avoid registering it in La for a while.

Or just getting all the formalities out of the way and getting a La plate before you go to NC.