Here is a quick cipher that you can try on your laptop at home (or in Peppard).
Assuming N51 and W000, the cache can be found at:
[j/k][jpj].i[o/l][jpk] i[lpl].j[l/u]m
The cache is a magnetic micro in the most obvious place. Please bring your own pen/pencil.
The listed coordinates are for a random point in a nearby wood and have nothing to do with the puzzle.
You can check your solution at:
...
***FTF*** Fast work wrightexplorers!