You need to use all 3 of the "steps" on the Meguiars...
6-polish-The second step of the Meguiars
From my experience, it works the best. ONLY prob I had w/the Meguiars is that it doesn't specify how to apply the clay (up n down vs. just rubbing it down) I have a black car..... Sooooooooooooo. Good luck. Take pics before and after.... Have fun and have a 12 pack because it's going to take ALL day.