Using prewire for aftermarket Sirius

[x3and5]

Working on taking advantage of factory satellite pre-wire features to help me "hide" my aftermarket Sirius wires (Stratus 5) on my 2005 X3 with (SA 693, DSP I believe) Business radio/CD. I've read numerous threads, shopped at MyRadioStore and I think I understand how to get power to it w/o cigarette lighter. Issues remaining:
1) I do NOT have an aux input on the front of the unit... is there an adapter/harness setup to take audio out from the Stratus 5 directly into radio/cd and where is it (what wires/connectors) on the back of dash unit? Or is it in the armrest (do NOT have cd changer unit or ipod there)?
2) My understanding is that PRE-WIRE includes sat radio antenna in the shark fin which means I don't have to run wire or stick another antenna on the roof... where at the front of the car is the beginning of the satellite antenna cable and how can I get it connected to the Stratus 5, cradled next to the dash unit?
Thanks in advance!