You may be able to just release the cable at the petrol cap end attach the new cable to one end and pull it through to the drivers side scuff plate (obviously you'd have to remove and release it at the drivers side to pull it through, if you have to apply to much pressure I wouldn't do this as you'll stretch the cable thus defeating the purpose).

Alternately start at the drivers side scuff plate and work your way to the back, removing each inner trim as you go 'both front and rear scuff plates, bottom part of the seat yadda yadda'.

__________________
[SIGPIC][/SIGPIC]