Plasti-dip is a very good and durable way to black out anything on your truck.
I have had my lettering dipped for over a year and the plasti-dip still looks like new.
Plasti-dipping grill and bumpers will get mixed reactions here.
Some love it, some don't.
Personally, I don't like the blacked out grill and bumpers. In my opinion, it makes the truck look like a work truck.
But if you like it, go for it!
Like I said, it's good and durable. A lot of guys even plasti-dip their wheels and it lasts on rims for a good long time too.