You need to find the fourth star. The locations of three stars
can be found on this page, somewhere.
GCBF5C7HDGC8EI8SE87OH6FCO8H78FUI867OESHONHFU
5DH5H56FFG5HJ87SGCB8OEUHZGC2PHHJB8HCD956SOSE
HH8FI6D7O8SUEY9IFOM87S4UDHY4IU4F78NHY98SGFGE
3NGCD6UIE6WOH8N7R6CUUE5JMH64878XHFE8HU8OICFH
HN76FU8IME7NSHFV67HGGYFE87IJ8XUDIHN6CIHFFHYE
Cache is a 600ml box. If you have the correct location, it
should be fairly easy to locate.
When you have a solution, please check it on GeoCheck:
FTF Honours go to stretch.kerr, whose final calculation
came within 0.001 of actual GZ!