If you don't want to splash out on a custom footwell-cladding phone console, or if you've got one, but use it for a phone not made by Apple, and want to hide the iPod/iPhone in the centre console compartment, under the arm rest, that's fully possible.
What you need to do then, is to route that last cable between the iPod and the adapter unit from the console compartment back through the rest of the centre console, and in to where you've placed the adapter.
If you've got a handbrake (some models have electronic parking brake), there are two points to consider:
1) Do _not_ remove the lever gaiter for it, as it's a pain in the <CENSORED> to fit it again. Removing the gear lever gaiter is sufficient.
2) Run the wiring along the _left: side (passenger side in UK and Ireland, driver side in rest of Europe - The handbrake is on the right hand side, both for LHD and RHD models.) of the centre console, together with the rest of the wiring, so the handbrake doesn't interfere with the cable, or (Heaven forbid) vice versa.
Further advice on the cabling:
* Start from the console compartment, and run the wire back the adapter. This is because the 50-pin iPod connector won't fit through holes, nooks, and crannies that easily.
On most iPod integration kits (including kits from Connects2, Dension, and Dice), the other end is a mini-DIN plug, which is easy to route.
* Undo the centre console screws on either side, and lift up the centre console a wee bit at the back, to make routing the cable easier. Make sure the cable doesn't get squeezed when fitting it back on, though.
* Removing some components up front may also be of help:
a) Gear lever gaiter (again: keep your hands off the handbrake lever gaiter!)
b) Ashtray - Open, and pull straight out.
c) Keycard reader and fascia - Pull straight out, flip the securing lever on the blue connector, and undo.
d) Air conditioning control panel - Pull straight out, undo the two modular cables and the dummy connector at the back.
Re-fitting these items are reverse order of removal.