For the RBP 2-pc grille, you have to cut the cross bar. There is only one other of the 2 window ones (from grilleworks i think, don't quote me though) and it's the complete assembly, all plastic and chromed, which you might want since you seem to like chrome
) For the 1 piece units you have to cutout the entire center section. Now, the guys from AAC (one of our supporting vendors) have one of a new line 1pc RBP grilles which is bad ass, you could contact them and see what they have to say.
Here's the write up I did on my 2-PC RBP RL install.