Well those that Ashley pointed out that I have are just overlays which I'm pretty sure the billet grille is practically the same.Is this what you have in mind?
Nissan Versa Forums - bboy_romeo's Album: My mods - Picture
If so, it just goes in front of the lower piece.
Where are you getting the grille from? Are they providing instructions?
They go right over top of what's already there and they send you tire wire to tie them on, but just check with the seller as stated above.