Prune honeysuckle

I have a Lonicera 'Belgica' that is three years old. It has not been pruned since it was planted as I wanted it to grow up to hide a neighbour's hot tub. Problem is, now it is over seven feet tall, four feet wide and top heavy. It is on a metal trellice that blows in the wind now. How much should I prune it back (ie. two thirds to the root, one third, etc). When should it be pruned? What would be another good way to support it? more...