Winterization techniques can be very model-specific IMO, so I won’t comment on the specifics for your model.
In general our mantra is “when in doubt, winterize.” Repairing a cracked pipe hidden somewhere deep can be very expensive!
Also, winterizing on the road can be much harder. If you have to winterize twice this season, that is more cost-effective than repairs IMO.
You might want to peruse this Winterizing sub-forum for more info:
http://www.airforums.com/forums/f458/
Good luck,
Peter