This past couple of years I have made buckets available (usually for about one day in three) and cut down the nuts. Like Kol, I minimise the hay to the doubles and triples so as to minimise rumen pressure on the lambs.
I use Lifeline and Rumenvite with fish oil.
I used to be feeding 1.5 lbs per ewe during the past week of pregnancy but now its around 0.5 lbs and with no noticeable difference to the lambs. In fact I think the ewes lamb just that little bit easier.
I do not feed sugar beet shreds until after lambing.