I tried to route the wires on my old avant, the trim has 4 or 5 torx screws behind the warning triangle flap and in the recesses along side it, it then needs a very sharp tug to pop the metal clips. Feeding the cables through the side of the boot is pretty straight forward, I taped the cables to some welding wire and pushed them through. Unfortunately I couldn't get the phono cables through the gaitor next to the hinge as they were too large so I got no further.