I believe sway bar and brackets should be bare metal for correct factory appearance. Many paint them to create this appearance and prevent surface rust. Regarding the lower control arms, some are using battery terminal protectant spray.....it hardens like paint. I used a product from Eastwood called heavy duty anti rust.....its cosmoline in a spray can...I drive my car about 500/year and never had a problem with stuff sticking to them. This topic has been discussed ad nauseam....i am sure others will chime in