Grand Sport Want to paint the inside barrels of mag wheels

[okgo]

I have a 2012 grand sport convertible looking to paint the inside barrel of mag wheels the outside is chrome but the inside from brake dust in stains looks terrible Does anyone know what they use at the factory like to keep it looking original

 

[bucwheat]

I just cleaned mine with joy then used a scotch brite pad to rough it up a bit then painted then semi flat black,two coats and they look awesome.