Hello vitux,
the black or brown wire is the ground (GND), that is the most right pin (near the floppy reader). But, if you mount this board reverse, nothing will be destroyed.
@all interested on this item (even they that have sent a request with the desired colors):
i need a month to receive new parts. I can't order much quantity, because i do not know if the parts come to me or not. There is another thread, that sell a similar part: if you wish to withdraw your interest on my sale, no problem!
Regards
Stefano