We have been planning to full time for some time now (4 years), finally went to SD and took care of our driver's licenses in December, registered our TOAD but did not purchase our DP until March.
We did establish bank accounts in SD as well and started transferring deposits to our new bank. This took a couple of months. We are slowly dissolving our local account using it for some final payments. We plan to be full time by the end of this month after house is closed.
It does take some time and we have been pleased to be able not to feel too rushed with the process.
We were able to get our SD agent to take care of register our motorhome so we now have SD plates on both vehicles.