The wax you use on your paint should sufficently shine and protect the grill as well. If you are worried about damage from stonechips or other road debris, a bra will help protect it. If you do use a bra everytime it rains make sure you remove it afterwards to let it dry. If you do not, when the sun comes out, the area between the hood and the bra will get hot and the water will try to evaporate and it can't because its trapped. This will cause a white hazy apperance in the clearcoat, and its hard to get out. Also if you are driving through a lot of dust/dirt on a daily basis I would not recommend a bra. The dirt gets trapped in between the bra and the hood and the bra will act like sand paper on the paint causing many scratches.
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