where to attach speedpulse cable in citroen picasso 56reg?

hi, i want to take the factory fitted cd/radio (siemans)out of my picasso and replace it with a 1din pioneer avic x1-bt sat-nav system. where do i connect a canbus cable for the stalk to work and also where do i connect the speedbus cable for the sat-nav, also is it true that i need to take it to my citroen dealer so that they can take the cd/radio out of the cars memory before i fit the new unit.