-1037, -264, -321 which is pretty close to the guesstimate above. And the description is right on. It is on the top layer of the temple, out in the open.
Outside, just above and north of the main temple entrance, just to the east of a lookout pillar on the northern temple boundry, between a kyv and an ixt. Eyeballing the loc: ( -1030.00, -265.00)