Replace AP50 System With Full Command 7039 W211

[Gordon R]

I have an Oct 2003 W211 E320 Cdi Fitted with APS 50 Navigation and Harmon Kardon. I have obtained a 2006 7039 Head Unit / DVD / Antenna and AP 5.1 DVD Navigation Disc. I don't have the telephone preparation but have picked up that my car may well be fitted with the Teleaid module with a multiplug under the centre cosole that will facilitate a Blue Tooth product now offered by Motorola. Basically is it quite a straightforward upgrade or is there any special wiring or pulsing required? And guidance appreciated - thanks Gordon