right mate, i done all mine myself, what you need to do is locate the grommit behind the glove box for the bonnet catch, get a metal coat hanger and push a hole through it, tape the wire to the other end and feed it through,
that's the hard part.
rest is a doddle, just run it under the plastic along the door and along the inside of where the rear speaker sits on the backseat then out the end at the boot.
don't run you're rca leads with the power cable, do the same for the other side or you get interferance.