having an awd just means its not mandatory to fit chains where those in 2wd will have to.
most important thing would be to make sure your cooling system is up to scratch for the drive up, and your tyres are suitable.
one afternoon at buller after having snowed all day, the last thing i wanted to do is dick around with chains so as i was awd i was let through.. i spun coming out of a bend on the way down and although we were sliding it was that slow my missus asked if maybe she should get out! slid maybe 5-10 car lenghts and wasn't till i hit the rough on the edge of the upcoming bend that we finally stopped.. newish ku36's wouldn't have helped but trick is to go very slow and brake early... test the abs lock it up and you will see how slow it pulls up.