Those that follow Pianotuna's posts and his exploits will realize this is not something new for him. He uses the latest technologies, solar panels, huge battery banks, etc for his rig.
Do you carry foam fillers to put into window and vent openings except for the couple needing to be cracked that will only need a partial cover? I think that is one thing that Sue T. did when they took their Class C to Alaska.
They camped with 15 Amp power for several days below -30.
What is your biggest worry? Freezing up, running out of tank storage, or battery power?
mike