Guildford game Mystery Cache

I was asked by El Ultimo Agave to hide this cache as its original hiding place isn't available. You will have to solve a puzzle to find it as it isn't at the given co-ordinates.

All kinds of sports have been played in this area over the years. In fact the earliest recorded game of one of them was played close to where the cache is hidden. This year (2011) the first game of the season was played on the anniversary of that original game.

How long ago was that? ABC years.

The day of the month? DE.

Who discovered this? The number of letters in each name F G H J.

The cache is hidden at:

N51 1(F-G).(A+C)(D+F)B W000 3H.D(C-G)(J-E)