This was the route I took, starting at the battery.
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_2981_zpsd93f6a05.jpg)
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_2980_zps010f0263.jpg)
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_2984_zps7d67e18d.jpg)
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_2982_zps426eb838.jpg)
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_2986_zps86f02a83.jpg)
I would recommend a dab of sealant round the cable/grommet to prevent any water entering the car (outside only)
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_3011_zpse17f4f7e.jpg)
This brings you in next to the fuse box, behind the glovebox.
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_2987_zpsd421fae9.jpg)
The footwell and kickplate trim just pulls off.
![Image](http://img.photobucket.com/albums/v679/baileydog/IMG_29891_zps29ccba10.jpg)
You can then run the lead to your amp mounting point.