Straight forward cache solve the Sudoku puzzle, replace the letters on the grid with numbers and off you go to find the cache.
Sounds straight forward
Here is the clue for the final cache co-ords
N52 31.ABC E001 02.DEF.
All you have to do in now is find the cache, this may prove to be very challenging.
You will need a small extraction tool and BYOP. Good luck!