An All-wheel-drive vehicle should get to within 200m of the initial GZ by travelling along the nearby pylon road (past the camel farm if coming from the Fossil Rock direction). A 4x4, quad, dune buggy or off-road motorbike should get to within 50m. There is room for trackables (and trading items) of a decent size however please leave the stamp and stamp pad in the cache - these are not trading items!
From the posted coordinates, count the number of red bands on the tower.
The letterbox cache can be found by walking in a Southerly direction (along the rock ridge line) - the number of red bands squared equates to the number of average adult paces to walk to reach the cache.
Hint - the cache is below your feet if you follow the above instructions and the ground beneath your feet looks like the spoiler picture!