This is a terrible job, pay someone to do it.
Now we have that out of the way, let's get on with it.
You can source a new bonnet release cable cheap on eBay, apparently it is a revised design, less likely to break. Yes, this is yet another one of those standard things that go wrong on a BF Falcon. One day you will pull the bonnet release and the lever will snap in your hands. The cable gets stiff over time, the plastic breaks down, it's life. You can pull the lug on the end of the cable to open it while you build up the strength to take on the job, all is not lost.
You'll need to take the front drivers side wheel off, and the plastic innger guard liners. They are held on with plastic clips. You can imagine how well they are doing after 12 years of road conditions, I think only one didn't break as I removed it. Don't be disheartened, we have ways. You can attempt to nicely take them out, it will only delay the inevitable. I ripped at them with pliers and screwdrivers, I reckon you will have better luck not breaking them if you are rough with them.
I still don't exactly know how the bonnet release handle clips on the bottom of the fusebox - the plastic on the fusebox broke while I was trying to get mine out. Which got it out, but makes it more difficult to reattach the next one. But again, relax, we have ways.
Thread through the cable in the same path you take the old one out. Check out the photos below. The only real trick was taking off the radiator support bracket so you can push the radiator out of the way to get the end through, and then sticking your hand under the plastic liner to get the cable into the bonnet release area.
Pop off the bonnet release catch, two 10mm socket bolts holding it in. Give it a degrease and re-lubricate it. I'm hoping for another 10 years trouble free...
Near the accelerator, hole out in the guard area. No plastic required to be removed inside the car other than the fuse box cover.
I don't know why, may different to the earlier model falcon, but the cable inner was about 20mm too short. I lost bark off my hands, nearly broke the thing and got very cross before I finally managed to get the cable lugs secured on both ends. "This seems insanely tight." Because it was. The bonnet wouldn't shut - the release was basically held open the whole time.
But no point being cross, I scoped alternatives and ended up moving the location of the mount inside the car to give it another 20mm of slack. This did the trick. It suddenly doesn't feel like it is going to last for 10 years though. However, worse case, the cable is much better now and if I had to remove the whole catch and just pull on the lug, it's easy. Yes, I tested it.
So now the fuse box part where the release lever clips into is broken. A self tapping screw through the fuse box plastic into the top of the lever sorted that out.
The inner guard and all those plast screws. Look, this is not a future resto job, it is a base model that if I get another 5 years out of it then I'm miles in front. Use some self drilling screws and make some new mounting points...
Brutal; but this ain't no show car, just reattach the plastic so it's doesn't flap around as you cruise down the street.
Around 3 hours of my life I can never get back, sure, the cable "was only $20", and the skin will grow back but I'm really getting to the point where some jobs - let someone else lose skin doing it for you.