That's the problem it's symmetrical, there is no defined left hand corner looking at it from the top, pins down rotate it through 180 deg it looks exactly the same. There is a clear plastic dot toward one corner it is not exactly over a pin and id taken it as a spruce mark from the casting process but I think now it denotes pin one. At the end of the day it is a component worth a dollar, it no doubt will tell me if it's not happy when I liven things up.
Mark K