When I was on active duty in the Navy and purchased a new car in California, I had two options regarding sales tax:
1. Pick up the car in California, pay California sales tax, then go through the paperwork with my home state to work out the tax transfer
2. The salesman and I drove just over the California/Nevada border, I took possession of the car in Nevada, complete with all the paperwork, then he drove back and I drove back. I then took care of the sales tax with my state home of record. (I did this option)
Unless the laws have changed, if you take delivery in California - you have to pay sales tax to them, then settle up with the state you license the car in.
Regarding our Model S - it is being home delivered by the Tampa Service Center on Saturday!!!!