I happen to own a house in Northern AZ where you can pretty much road register anything that has wheels attached in a somewhat safe manner.
Ross had the car road registered in CO, so it is titled and a no brainer. Unfortunately it would be problematic to register the 11 in CA since it does not have a speedometer. I would need to add one of those at least temporarily showing at least 7500 miles to register it in CA.
In addition, Northern AZ has some great twisty roads which is what the 11 was made for. From Prescott to Sedona via Jerome..
.the cops should hear me coming. No traffic lights either for the most part.
If it is registered in YOUR name in AZ (or any other state) then you can register it here in CA in your name. You moved.
If the car is 10+ years, the mileage doesn't matter and you do not have to report the mileage either.
07 Lotus Exige S Chrome Orange
05 Ducati S4R
02 Suzuki SV650
09 Kawasaki KLX250