Hi,
It's not the plug that is displayed in the manual, but the power socket (the connector on the device itself). So, if you look at the device's panel where the socket is located and the device is not upside down, pin 1 is on the top left-hand side.
And of course, the pins on the PSU are mirrored, i.e., if you face the connector pins 1 & 3 are on the right, while 2 & 4 are on the left.
DM