Cache is not at posted coordinates but is less than 1 mile away.
Bemis Memorial Park is more than likely the spark that started the town of Spencer. A great deal of history occured on this soil. Now lies 2 memorials of the history of this place. These are where the info you seek lies. So like any good history puzzle cache, let's see what we can learn!
Samuel Bemis
K-1=A - In honor of Samuel Bemis the Knd settler of Spencer.
L-3=B - In 1L21 near this monument he built a log cabin and later the first frame house in town.
M-8=C - He reared a family of M children.
N-5=D - Samuel Bemis died in 177N.
O-4=E- He was 8O years old when he died.
Capt. Edmond Bemis
P-5=F - Son of Samuel Bemis; he settled near this place in 17P0.
Q-4=G - Served in the French & Indian Wars, and was a lieutenant at the Reduction of Louisburg in 174Q.
R-6=H - Captain of a Spencer Company in the expedition to Crown Point in 1755-R.
S+0=I - Born at Watertown 172S.
T+3=J - Died at Spencer 18T0.
The final can be found at...
N 42 AB.CDE
W 072 FG.HIJ
Congrats to JustPlainPhil and MtnProf for their CO-FTF, and for finding and returning my sunglasses!!!

You can validate your puzzle solution with certitude.