Through the hells mouth, to the circle of bones, into the halls of wisdom kill a streaker, kill a knight and 3 a colors, on the path towards the next door turn right it's on the other ledge closer towards the left.
-
Alright When u first see the hellmouth (after turning right of the building u 1st have go scan) Go right, if you hug that wall there should be a large crevice walkway that reveals several outpost The ghost should be in one of the posts to the left