Placed with permission of GPHC #140810-04 Please follow all park rules.
The coordinates bring you to the sign "Donovan K Hopkins". From the sign you will get clues to the final cache location nearby.
The final is at:
N39 08.A22
W84 20.4BC
Where:
"From 19BX to 201A Donovan K Hopkins spearheaded...."
".. to acquire Y00 nature preserves..."
C=X-Y
Sum check A+B+C = 17