Leave Car at port parking while sightseeing?

I posted this in another place with no replies. Hope someone over here can help :)

We will be cruising in & out of NOLA October 3-8. As soon as we get off the boat(10/8), we want to spend the day sightseeing. My question is this, can we leave our car in the Erato Street Cruise Terminal or Fulton Garage, spend the day sightseeing & then return in the afternoon to pick it up?

We'd like to use streetcars & walk as much as possible because it's too much trouble to find a place to park & drive around town (so we think).

Can't answer you about the port parking, but I would imagine you could leave it at Fulton Street Garage. When you book it online just give a later time on debarkation day as to when you will retrieve your car. I believe they might charge for an extra day, but it would still be cheaper than trying to find elsewhere to park.