This cache is a multi at Poplar Gap.
The final is at N 37 13.ABC W 082 09.DEF
The checksum is 39.
For this multi A=1 and Z=26
We will only be using the first word in the top left corner of the sign.
A= first letter - 16
B= fourth letter - 2
C= seventh letter + 3
D= fifth letter - 9
E= second letter + 3
F= third letter - 3
Fznyy ybpx obk nzbatfg fbzr ebpxf ng gur onfr bs gur ohfu.