The 'left' side (with the connector pointed away from you) Or, if you prefer, 'left' side, closer to the screen
Scroll about three quarters of the way down this thread and study the photo with the BIG RED CIRCLE around the connector.
http://www.misticriver.ne...es-faqs-3.html#post363259
Follow the instructions here and you should have no problem. As you'll see, you can swap the wires by lifting the 'catch' on the connector with a thin knifeblade and gently pulling them free. A surgical clamp works well to hold the connector, while you're doing this.
REVERSE POLARITY CAN KILL YOUR PLAYER!! Check and doublecheck!
Good Luck!
piscator