I'm finishing up my loan paperwork right now, so I haven't actually taken delivery in Louisiana but:
Delivery Adviser warned ahead of time that I would not be receiving temp tags as LA is a self registering state due to Tesla not having a sales license here.
You should be receiving all paperwork to title and register the car within 7-10 days of delivery. (Unless your financing bank has asked that the paperwork go to them)
I wanted to self register and pay the taxes myself but my bank has insisted that all paperwork go to them and they will take care of titling and registering.
Since I knew I wouldn't have a temp tag, I asked if they could supply me with one. To my surprise they said yes, so that takes that off my plate. So I would suggest, if you financed, see if your bank can issue temp tags to you.