Make your way to the given coordinates. Here you will need to gather some numbers to give you the final coordinates for this cache. You will see a bench dedicated to 'Bob Cheshire', please read the plaque on the bench and use the numbers as follows:
Year of birth= ABCD
Year of death= EFGH
Cache location:
N 51 F (C+H) . E (D-C) (B-C)
E 001 A (B-C) . F C (B-E)
BE CAREFUL AT FINAL GZ NOT TO BREAK TOO MUCH OF THE SURROUNDING PLANTS AS IT WILL EXPOSE THE CACHE