Thank you 'raleedy'. Since the manual only suggested 'fine link' chains, I asked the BMW parts dept and they suggested a type of cable chain that is easy to install. They were able to order them from an outside vendor for less than $100; for that price I will keep them even if I don't use them on the trip this winter. If the weather looks ikes it will be bad, we will go the 101 route anyways.
I was thinking about the SC pickup but couldn't adjust my work schedule. That must have been a great trip!