Where are the 3 Stonehenge skulls in Chichen Itza located?

Hi dar,

From MaG's walkthrough:

Chamber with side halls: At main chamber hall, turn to face the opening (exit from chamber) not entered yet. Turn right and pan down, pick up Stonehenge skull #1 by the pillar engraving.

Skewered Skeletons room: So this is where the prisoners are dropped from the ceiling to die. Pick up Stonehenge skull #2 on the floor.

Luminous Pool: Deep part of pool - Look around to pick up Stonehenge skull #3.