Near the posted cache waypoint, you will find an imposing natural landmark. Approximately 2.5m southwest of that landmark, close to the ground, you should find a tarnished (i.e. hard to see) copper plant tag attached to the bottom of a fence.
You will find two numbers stamped into this tag. Replace the lowest-order digits of the North coordinate of the waypoint with the first set of digits, and the lowest-order digits of the West coordinate with the second set of digits. This will give you the coordinates of the second waypoint.
At the second waypoint, there is an obvious object. Two numbers are embossed into another copper tag glued to this object (they used to be pencilled onto the object, but weathered off every few months). Proceed to modify the waypoint like at the first stage.
Note as of a maintenance visit in April 2018, there are TWO tags glued to the obvious object, on opposite sides. If both are missing, look for them on the ground. If that's still not enough, look for the extra backup tag on the huge tree about 20m to the west of the obvious object.
You now have the location of the cache. The cache is hidden completely out of sight, buried by a few pieces of rotten wood in the cavity underneath an old fencepost that has fallen over. The final waypoint is a few metres off because the cache was originally hidden in another spot, but you can't fail to find it since there are only a few candidate fenceposts nearby and the right one is the closest one to the waypoint. Please leave the cache well hidden and well sealed again. It is a mason jar, so don't bring anything big to put into it. Also, do not, and I cannot emphasize that enough, do not store anything edible, regardless how well packaged. Critters have incredibly sensitive noses and will trash / drag off any cache that intrigues them.
The cache contains miscellaneous knick-knacks, hopefully you will enjoy one.