From the pictures in this thead (particularly AP-36x-MNT-H2-1), the signal is directed from the side with the Aruba logo printed on it. So if you intend to hang the 367 over the side of the building horizontally (ie facing down), and the users you are getting coverage to are below the AP, then you should be fine.
The MNT-H1 is another option that provides an articulated joint so you can dial in an angle between horizontal and vertical, if your coverage need is not directly below your mounting location.