At GZ, you will need to find a sign with two words. The sign also has a sternwheeler boat on it. Let the first word of the sign be ABCDEF
P = A - C - 1
Q = B - D - 1
R = E - F
S = E - C
T = C - D + S
U = A - D - S
The cache can be found at N 49° 23.PQR' W 121° 25.STU'
You can validate your solution with certitude.
This cache was hidden as part of the fourth annual Fraser Valley Cache Bash. For more information on this event visit http://fraservalleycachebash.brilang.com/. The theme for FVCB4 is "The Unexplained".