The co-ordinates given are not for the cache site, they are for a memorial near the village of Bradfield Southend in Berkshire. You will need the numbers of some of those remembered here.
You should find the digit sum of each number, by adding up the individual numbers until you have a single digit. So for a number of 43523, you would do 4+3+5+2+3 = 17, then 1+7 = 8, so 8 is the number you need.
A digit sum for Albert Little
B digit sum for Ernest Green
C digit sum for George Cripps
D digit sum for Edwin Hall
The final number can be found at the village hall.
What time will the gates be shut? Subtract 2 to get E.
The cache is at N 51 CB . ED(D+E) W 001 0(C+E).E(D-C)(A-B)
There is limited parking in a lay by near a bus stop at N 51 26.271 W 001 08.251 or you could park in the village and walk back. Be careful of the traffic on this road. This village is worth a visit after dark in December. Contents: the usual swaps, a World Diabetes Day Geocoin, and 'Going to Denmark' TB