I also have an E90 328i and have been trying to figure out which part numbers to order?? I have come up with 3 different ones, the latest I have is:
SIRIUS Receiver(PN: 65 12 9 192 274)
Installation Kit(PN: 65 11 0 432 318)
Trim Panel(PN: 51 47 7 070 549)
you also need to have 0693 Satellite radio preparation option installed. There is a DIY for if you don't have it, but just a little more work.
2008 328i ZPP, ZSP, Xenons, BMW Performance Intake, Performance Exhaust, OEM Blacklines, MTEC V2 AE, Performance Pedals, Hankook Evo's, F1 Ceramic Tint