The cache is NOT at the posted coordinates.
I've decided to do some simple puzzle caches to encourage other people to give them a try. The final location will be pretty easy to access.
The Wisconsin earthquake affected Alaska with a maximum Mercalli intensity of VI (Strong), causing a destructive basin wide tsunami, leaving 165–173 dead on May 6, 19AB.
Final Location is: N38 47.3B(A+1) W121 18.AAB