Nav update for 2005 997 with Pcm

[mbruen]

I have been reading forums / etc. and am confused.

I have a Pcm head unit in my car (2005 997) with a Bose option. does Porsche make an upgrade to add the nav unit to my existing PCM head unit? I heard you have to add a card or something to the base unit plus an antenna and cd reader in the trunk.

I heard an upgrade kit may have just come out. what is the part number?

I have also heard that since I have a Bose option I have to replace the entire head unit ( very expensive ) . Does anyone know the details?

Also, are there any secondary sources of due to it's newness can we only get it through a dealer?