The grill outer panel(I assume you are talking about the entire headlight surround piece that accepts the center grill)should be painted body color. The front fender trim is incorperated into that piece and doesn't look right painted anything other than body color.

Paint the plastic center grill flat black instead of gray and the front end will look great. I also don't think it looks right when guys paint the Rallye hood inserts black. They should be body color as well. There is a small center piece that goes inside the hood louvers that I have seen people paint orange instead of just body color and that look prety good. This is just my opinion and you do what ever you want to YOUR car.