Slitherlink Cairo Mystery Cache

In the Cairo tiling, all polygons have five sides.

To work out the location of this cache, you need to do the following:

1. Solve the puzzle below (see the cache listing for Slitherlink Boot Camp for the rules about how to solve Slitherlink puzzles).
2. Locate the letters a through to t in the puzzle (l and o are omitted). For each letter, its numeric value is the number of lines around the cell.

The cache can be found at S 43 31.ABC E 172 33.DEF, where:

A = a + b + c
B = d + e + f
C = g + h + i
D = j + k + m
E = n + p + q
F = r + s + t

The checksum for A to F is 34.

The cache is a small pill bottle attached to a cable tie in the corner tree. Head-ish height, around the back. Handle with care; it's attached to a very slender "branch".