Exposure therapy is one of the most effective known treatments for phobias, it involves "exposing the target patient to the anxiety source or its context without the intention to cause any danger". With this principle in mind, this two stage multi has been specifically designed to treat acrophobia, herpetophobia and claustrophobia (if you actually do suffer from any of these phobias, then this probably isn't the cache for you).
The best place to begin is from behind the Cowan Community Centre. To get to the trail you will have to go around a wire fence, but don't worry, you're not trespassing. I think the fence is a remnant from when this area used to be a quarry, now it's just a regular firetrail with slightly fewer trees than the rest of the bush. Just in case I'm wrong about this, you can also access it from the trail that starts at Alberta Avenue, I've listed the coordinates as a trailhead. The better parking spot now is just off the Pacific Highway, there is a large dirt verge with plenty of room for 2+ cars. See new waypoint 'alternate parking'. You can walk to GZ along the firetrail here to within 50m.
STAGE 1
The terrain rating of this cache is almost 5, because it almost requires special equiment to reach it. If you consider yourself a good climber, then you may not need any additional equipment, but alot of people will. That equipment may be climbing gear, it may be a camera equiped drone (if you're a confident enough pilot to fly close to trees), or it may be a really long selfie stick, how you complete stage 1 is up to you. At stage 1 you'll find a wooden sign with 4 numbers ABCD. These can be used to find the coordinates for the final stage S33° 35.ABC' E151° 10.DAB'.
The new WP1 is a punched aluminium tag approximately 4m up a tree facing upwards. As suggested above, if you have a camera equipped drone (with a very good camera) and you're confident enough to fly close to trees, go for it. Most people will do it with a ladder, and a selfie stick may work if you can get one that long.
FINAL STAGE
The coordinates have been measured as best as I was able, but even assuming perfectly accurate coordinates, you won't have much luck if you limit your search to directly around GZ. Try searching about 10-15m north of where your GPS is telling you. Also you'll need a torch, any old phone torch will do, and wear clothes that you wouldn't mind crawling around in the dirt with. The cache container is far from water tight, but based on where it's placed that may not matter, then again I'm really not sure what this place will be like when it rains. So let me know if you see water getting into the cache or if dirt and grit is making it tough to open and I'll replace it with a regular container, or if it happens to last a long time I'll make a new one. To open the cache, just twist the top, don't try and pry it open this might break it. The cache is no longer screw top, just a generic ammo tin.
WARNINGS
This cache does present a lot of risks, if you're not confident in your ability to get to the cache safely, then you should just leave it for another time. There are also certain areas around the final stage, where the ground may not be stable, so watch your step and for this reason, I'd recommend that you only send one person in to get the cache at a time. There are also a lot of snakes in the area, I most often see red bellies, but even as I was placing the cache, I saw a green tree snake slithering around just outside GZ. I know they're not poisonous, but you wouldn't want to encounter any sort of snake while making your way to this cache. The snakes probably enjoy eating all the leaf-tailed geckos (of which I'm sure you'll see plenty).