[s-cars] Wiring connections for hands-free phone, etc.?

[Doug L]

Friends,

My UrS4 rolled past 100K this past month and I thought it 'bout 
time I re-acquainted myself with modding.
Can anyone reference where is the easiest connection points for 
radio mute, ignition power, and possibly the existing telephone 
speaker? I've saved all the accessory work for the same major job 
(Satellite radio, Siemens Hands-Free, and a PocketPC Navigation 
system.  Any help is better than digging through the Bentley 
Wiring diagrams and trying to match the wire colors and 
locations!

Thanks, Doug L
94 S4
92 500E