In order to locate the actual cache you will have to carry out the
following calculations:
If you were standing at the posted coords the cache is on a true
bearing of 225 degrees. If you were standing at 'Howzat' (GC15KHD)
it is on a true bearing of 311 degrees.
Where these two bearings meet you will locate the cache.
As an additional clue, if you were standing at 'The Leper
Colony' (GC11ZFT) it is approximately 13.2 km away.
You will need to be fairly accurate in your calculations, due to
the distances of the reference points, otherwise you could be a
fair distance out. To that end I have also included a Geochecker
link that you can check your coordinates on. The accuracy on this
link has been set to within a 30 metre radius and I would strongly
suggest using this link prior to going and looking for the cache to
avoid dissapointment
Geochecker link
Once the coordinates are calculated the cache itself should be a
fairly simple find. Some well formed dirt roads and a small section
of a secondary tracks will lead you to the cache. 4WD may be
preferable in the wet season.
Good luck and enjoy!