Turn left signposted Wythop Mill. After a few hundred metres you will see St Cuthbert’s Church on your left and a private lane opposite. Turn right up this lane and Brook House is the first house on the left. Just over the bridge is a parking area for The Lazy Fish.
So, google St Cuthberts Church gives us a OS Map reference, NY163295. You can't enter this on your TomTom, so then I found a site to help convert from OS to Latitude and Longitude.
This gives us 54°39′14.69″N 003°17′53.01″W