E90 and E92 have different housing. Can you tell us which body the mirrors are from?
(E93 M3 has matte black housing so I'm thinking it's not from E93).
And.. make sure to post them on E90Post side.
They tend to like to install M3 parts on their rides.
PAST: 11 E70 X5M | 08 E90 M3 | 08 E92 335i | 03.5 E46 M3 | 99 E36 M3