At the posted coordinates you will see a sign. There is a bylaw number shown on the lower right corner of the sign.
Assign the bylaw number to the following letters ABCD-EFG
The final stage for the cache can be determined as follows:
North : 43 5(A).(A+E)(D-E)(E+G)
West 79 1(A).(F)(D)(F+G-A-D)