There are two stages to obtaining the final coordinates. Starting at the first coordinates, note down the numbers on the sign: ABCD
Move on to the Blue Pill to grab the eastings coords
Northings can be calculated as: N51° 49.CBD
Finally pop along the last leg to grab the prize.
Cache is a 1.5L Clip lock container with a Log book and pencil.
Enjoy the walk. It is a lovely one. You could start in Sawbridgeworth Town centre and take in Sawbo-Lock and Sawbo-Stort along the way. Alternatively, park up near Kecksy's farm and start very close to the starting point.