W203 C class: phone car kit and stereo

[cj_eds]

Does anyone have any experience of fitting a car kit to a recent C-class? I'm trying to fit a Parrott kit, but the stereo lacks an ignition signal. The Parrott only needs to be powered when ignition is on, but the Becker head unit appears to use the permanent 12v supply and my guess is that it must receive ignition status from elsewhere over an internal CAN or something?
Anybody know where I can get the ignition from easily? Is the easiest solution to run a cable from behind the key barrell or is there an ECU thats got the ignition source a bit closer to the centre console (and is easy to get to!)

Thanks!

[Hooli]

not familiar with the car but the cigar lighter is normally ignition switched.

[cj_eds]

Probably a good place to start, thanks for the idea. Don't think its on a delay like a lot of the other stuff. Should be esay enough to run a cable down the transmission tunnel too.