It is easiest to replace if you took your fender off. In fact it is self evident how to do it then. You will need to get two plastic retainers under fender to hold it (I never was able to remove existing ones w/o damaging them). The rest of plastic retainers (on the bulkhead) can be taken off easily w/o damage.
w/o taking fender off:
you need to pull out old cord (you basically unscrew the release lever, cut the cord from inside, pull out rubber grommet that plugs hole in the firewall, and pull the cord out from the outside). Then thread in new cord from inside the car, when you need to catch it from the hole in front which is tricky thing to do. This way of course you bypass the retainers under hood, which is not important - it will work w/o them.
You need to take hood latch out in order to attach the cord to the latch properly. Take marker and mark the contour of the latch on the bulkhead, so you know how to position it in the same place when you reattach it.