Professional BT installation in So. Cal.

[sandiegoX5]

I have a 2002 4.4 X5 with a 3/02 build date and a navigation system.
I asked my dealer how much it was to have bluetooth retrofitted. He tells me that it cannot be done -- only X5s after 4/02 can be retrofitted.
I know that is not the case based upon posts I have read on this site, but it was not worth discussing with the dealer.
I would really like to get bluetooth installed, and I do not the time or aptitude to do it myself.
Can anybody give some recommendations for installers in Southern California, preferrably San Diego?
Thanks in advance.