At the posted coords, you will find a number. You will know you have found the correct number when you find it. Take that number and replace XY with it.
The final cache is located at N 35 1.8AB' W 80 57.9CD'
AB=XY-9 CD=AB+X EF=AB+XY
Please log the cache with 'Found It!" or "TFTC" or any other meaningless log.