1. You need to remove the bezel around the shifter, the chrome ring around comes off first (providing yours is chrome), then the outer piece of the shifter bezel needs to come off. The you can remove the center stack bezel. Some models may have a screw in or near the coin holder/ash tray. That would be the only screw holding the thing together.
2. No secrets taking the console out, i believe that two screws are exposed when the shifter bezel is off and there should be two more inside the console at the bottom.
3. You wouldn't be able to tap into the radio to keep your XM on when the key is off like the radio. The radio receives its 'wake up' signal over the communications bus. The radio itself has no switched power going to it only constant B+. The radio turns itself on and off via the communication signal it gets. And there is no power antennae output.
4. There are several audio inputs built into the 22 pin connector on the back of the radio, but I believe that the radio will ignore the inputs as they are for the Satellite radio, hands free interface, and the media system. If you are not equipped with any of those, I think that the radio will ignore those pins. You could get the IPod interface kit from Mopar, no exposed wires using that.
There really is not much help here the newer the vehicles get the more complex and harder to integrate aftermarket components into them.
Dodge/Chrysler/Jeep Technician 14 Years
ASE Master Certified
L1 Advanced Engine Performance