I have pointed out (even circled) the serpent pillar at the first image. I use UOCartographer (not tilted, EC map) and the map together. The treasure maps are actually 50% resized versions of the actual maps (using nearest neighboor algorithm), so you can take a screenshot, zoom them and use a half zoomed uocartographer screen and add a marker at the point the needle is pointing.
For this particular map, I just aligned the serpent pillars and added a marker at the point the needle is located at uocartographer. Petra added a more detailed image on the treasure hunting page of stratics. For the digging, I just target the map with a shovel then target the water. You should try it yourself.