The headline coordinates take you to the phone box. The information you need is inside and from the Hatherleigh specific notice.
As it has gone missing. This is the information you need for the phone box part of th equation.
WORKING PHONE BOX
PLEASE DO NOT DEPOSIT BOOKS
THANK YOU
HATHERLEIGH TOWN COUNCIL
Number of letters in 2 nd word = A
Numer of letters in in 1st word = B
How many "J's" are there in 3rd row = C
Sum total of letters of both words in 3rd row = D
POST box info needed :
1st digit of time of collection on Saturday = E
CHECKSUM ABCDE = 29
The cache can be found :
N 50° 48. A B C W 004° 04. D ( D-B) E