The co-ordinates take you to a thatched cottage a short walk from a pub car park and the cache is to be found in open counrtyside after a pleasant walk along a track and out into the fields.
The puzzle is solved by substituting the letter values in a game of Scrabble for the letters below, the N and W should not be substituted with anything, this should give you the co-ordinates in a standard format.
The cache is at N KT [M+D][P+P].ADX
W [Q-Q][Z-Z][H-H] A[M+Y].[V-V]J[C+C]
The cache is quite a large cylindrical pot just a few steps off the path.
Oruvaq naq ng gur onfr.