nothing like a little plastic paint to clean them up and make them shine... mine looked kinda like that before i hit them with some Krylon Plastic Fusion Gloss Black... dont seem to have any before pics but you can see them shine in these pics
this is shortly after i first painted them about 2-3yrs ago... (note the bullet in the grille that justin now owns.... oh and the spots... bugs and dirt)
and here they are still shining after a year in the sun and several baths later