I want to do this too...missed this years (its in a few weeks) but next year could be good :)
I think the only thing you really need to think about is snow chains - min 1 set, poss 2 and they have to be good ones, not cheap crap. Then make sure your system has the right oil for low temps and enough antifreeze in the coolant system and screenwash.
Other than that youll be fine as standard apart from needing MT's as a min requirement to enter. Diesel in places where it gets cold has anti-waxing agents in it so when you fill up over there itll handle the cold ok, and also even "winter" diesel in the UK has them to a lesser extent.