I'm am in the market for a black grill and black grill inserts for a 2016 Renegade. I would also consider trades for my current silver grill and chrome inserts.
I suggest using Black Plastic-Dip spray can. Tape off areas and rattle can it matte black for cost of $10. If it comes out crappy you can peel it off, or take off area's that ran/dripped. Let it dry to see how it comes out (bubbled up areas will fill in) I have had it on my grill going on 3 yrs. I do avoid direct spray during car washes.
