I have a 2005 E500 Wagon that I ordered last year and took delivery of in January. It has the Premium Package that includes the Harman Kardon radio system with navigation, etc. Many press releases have bragged about the fact that all 2005 MBs come w/ Sirius satellite radio and mine has a SAT button but I have been unable to find any activation code to use w/ Sirius.

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When I spoke to my dealer they wanted to charge me $1,000 in parts (receiver and antenna) plus $300 labor. I certainly don't want it that bad and I feel misled about what the car actually has that supports satellite radio. In researching this further I found a link on the mbusa site that says seems to support the dealer installed option opinion but lists a lower price for the parts:

Any pearls of wisdom? Is there a more cost effective way of getting Sirius integrated w/ my factory unit (no aftermarket add-ons)? A good source for the parts? Any documentation on the installation? Is it a reasonable project to do myself given good mechanical abilities but no special MB-related tools or experience? It seems that the kit includes an unsightly black blob of an antenna that dealers usually drill a hole through the decklid to mount and many owners use aftermarket units. Any idea what the antenna solution is for a wagon? Have they figured out a way to combine the nav and sat radio antennas yet?