Valenki,

Just mount the CPU behind the center console on the floor in the back seat area OR get creative and build a small enclosure for it. Then just route the wires under the center console and carpet.

As for the AMP power wire. run the wire from the battery up along the passenger side quater panel. There is a lip inside the engine bay you can neatly tug the wire under. Take that all the way to the back of the bay and along the fire wall to the driver side. Right about in front of the stearing wheel, there is a small hole with a ribber gasket around the inside. There is PLENTY of room to tuck several wires through there (fog lights etc.) then route it to your components.