Takes some work, easiest way is to fibreglass the centre VR part to your original VN headlining.
Or, start cutting things trying to make it fit.
I recommend the first one, been trying to get my VS Caprice headlining to fit properly for a few years now. Pretty much given up at this point. Check out MEANVN's thread, he did it the easiest way.
Has yours got a sunroof?
Or are you ever planning on getting one?
I don't recommend trying to fit the Caprice Headliner if you do. Too much hassle.
I want a sunroof (probably dreaming) but because of the Caprice headliner, too hard
If you can fibre glass, I would recommend that route, you'll need to retrim it, but it'll fit a whole lot better.
If you do install one that way, some extra brackets in the roof, between the roofs ridges/supports will be be needed to hold the weight of the roof.