I think you're referring to the hitch pin box.
The paint on mine faded so I used a 3M scotch brite pad to remove any flaked paint and rough up the rest or the hitch. I then cleaned the surface thoroughly with Prep Sol. After masking off around the area to prevent overspray, I used a can of semi gloss black spray paint. I also used painter's tape (the blue stuff) to mask off a couple of decals that were on the hitch with instructions.
Looks like new! Good luck.
BTW, don't try painting it on a windy day!
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