The cache is at the posted coordinates!
Welcome to Dee Why! Here you can swim, walk, admire views or find difficult geocaches. Clearly you're here for the last option.
To get to the start of the ascent park on the north end of the cliff, somewhere around the parking WP. Then go down to the bottom of the cliff and start walking to GZ. You will need to traverse some fishermans ledges to get here.
Check the images for a spoiler photo of the cache. It is a square sistema in a horizontal crack at the end of the ledge. You should be able to see the cache before attempting the crux of the climb. The cache has a soccer ball stamp in it.
There is some pretty advanced climbing involved here, couple this with the height (around 10m) and this is a cache not for the faint of heart! Use ropes if feeling uncomfortable!
GLHF - GHHH