At the above co-ordinates you will need to find:
Details on the Post Box top telephone number : 03457 740 A B C
The Postbox number: WR11 X Y Z D
The cache can be found at:
N 52 05. ( B + X + C ) ( A - Y ) ( Z - Y + X )
W 001 50. ( B + X - Y ) ( X + B ) ( A - X )
The Fine Pair series was originally started by wizardsmum but is now managed by mattd2k.
If anybody would like to place 'A Fine Pair' of their own please do. I would just ask that you first visit www.afinepair.co.uk to request a number to avoid any duplication.
mattd2k also keeps a public Bookmark List of this series. Once your cache is published please contact him via at geocachingafinepair@gmail.com to have yours added.