Dog Tired Mystery Cache

The cache is not to be found at the above co-ordinates, but is actually located less than one mile away.

The true cache location is given by:-
North 50 (F plus A1). (B + U) West 000 G. ((V times A1) + R

A correct solution of the puzzle will give you a checksum (all 15 digits) of 48

Please note that, on 28th Jan 2011, the cache needed to be moved by about 10'.
A new formula has been provided, but the old formula will still get you near enough to find the cache.