Turtle wax makes a car kit called "black box" I used it on two of my cars and it worked great. It takes a long time to apply since you do it in 3 stages. Its like waxing your car 3 times. It will make the black look better, but wont do much for the scratches. For those as long as they are minimal use some polishing compound before using the components out of the black box. You can use rubbing compound before the polishing, but the coarse rubbing compound is very hard to shine back up on a black surface so I don't usually use it.
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