These are the bars that go across the front grill.
There are 3 pieces. Others have mentioned just pulling on them to
remove them. If you do that, chances are you will break a tab or two
from them.
This is a safer way to remove them...
1) this picture shows the tools used and one of the removed pieces.
Notice the tabs circled in red.
2) You need to locate where the tabs go into the grill.
To remove the pieces, use the "L" shape screw driver
(or any tool in an "L" shape) to go behind
the grill and push down on the tabs as indicated on the down arrow.
At the same time, pull out the piece by hand or use the paint can opener to pull out the
piece.
3 tabs on the left and right pieces.
5 tabs on the center piece.
NOTE: 2 tabs on the the side pieces have solid grill behind them.
I just pulled those by hand. I did break one tab in that process.
3) Repeat for the 3 pieces.
This is how the grill looks like after you remove a piece.
Why remove these pieces?
1) if you have the black ones and want to install the gray ones that come
with the 330.
2) if you are installing a spoiler. (that is my case)