In general pearls go over an existing base color. Metallics are unto themselves, yet tone or let down are effected by the base color. I.E. a white base under a metallic red yeilds a brighter finished color vs a black base, or straight silver under metallic blue, etc. Pearls are mixed in clears whether dry or paste. PEARLS GO A LONG WAY!! Many an over zealous painter trys the some's good, more's better gig with pearls and it will kill the final look. Test panels and conservative application rule with pearls for maximum effect or "flop". Usually 2 uniform coats and maybe an extra coat on the areas that see the most light like body lines or roof corners. Then normal clear topcoats wake up the pearl and keep it protected from UVs.
For the rims, single stage black with a flattening agent added to achieve the final look would work best. Once again a test panel is required to get it right. Use as little mat'l possible on the rims to avoid cracking and chipping later on. If the rims are no big deal, and just for color, as cheesey as it sounds, Krylon semi-flat works very well. Real durable and covers quick without too much build up. Good luck with it.