Probably this has been included in some of the Mega Packs that are there at the forums / repo, but I didn't find it so I've done it myself.
This is a very small, simple mod that adds some new grille and bumpers to remove the "squares" that are in the grille, like in the Pessima for example, take a look at the pics and you'll see that are simplified, the vertical "sticks" have gone.
This mod doesn't come with any config, at the spoiler below this text you have pictures of the content with the NAME of the part you have to select.
Beta Sport Bumpers and Grilles 0.5
A small modification to your car that can be done at home and upgrades its looking!