Put it in the trim! Run it through your firewall with a grommet... then run it along your panels and under the floor carpet to the rear (amp).
^ correct, or if the amp is small enough, run the wires under the carpet into the cabin,and put the amp under the passangers seat or something..
That one is always nice too. Stay creative with it. Doesn't really matter where you put the connection wires, as long as they are connected, look neat and function right?
how do u get it from the cabin into the trunk, where the rear window is? if i take off all the back panels will i find a way?
Well here it is: You have to find a way to make a small hole (drill) behind your back seat. Or you could just take your backseat out, make a hole in the trunk cargo compartment's wall, and string the wires through there. Try taking panels out too, usually there are little holes there already. I have an EP3, so I don't have to worry about the the trunk wall.