I take it that you're talking about the Silver that came from factory? and you're after a very clean look... that look can be achieved by using Mercedes Brilliant Silver (744) as the base coat colour, however their is a trick to get the "look" just right! and that is to paint the wheel faces a very very light shade of Grey, almost White in fact, then apply the silver in very thin coats, until the light Grey is only just covered, wheels should be painted face up, so the silver dries uniformly, center caps (if applicable) should also be given a coat of silver, in the final stages of painting the silver... place the caps carefully on the wheel, and give a few coats of silver... remove, and Lacquer separately, keep the caps paired to each wheel, to ensure a perfect colour match...
HTH
Thom
