Both pics are after two passes with car shampoo and clay bar. The first pic is my bumper, some of that is rock chips not sure what the rest of it is exactly but it's not coming off easily. The second pic is what I assume to be the result of bird poop that stayed on too long. Again tried shampoo and clay which didn't touch. Any specific product recommendations or techniques are appreciated. I just ordered a PC and the dual Wolfgang combo but I want to prepare the paint are thoroughly as possible before I do that.
