I don't think you do. But I'm pretty sure you have to keep it lighter than... what is it 3.5 tonnes?
And you can't go over 50 in an NSL, but I think if it's a white van it'll be limited to a minimum of 80.
Limited by law to 50mph on single carriageway NSL and 60mph on dual carriageway NSL.
Get used to driving 1m off peoples bumpers, a copy of the Sun for the dashboard and keep your foot welded to the floor at all times.