Speaker Wire Polarity

After much research I couldn't get a definitive answer on which of the standard speaker wires was positive and which one negative. They are all different colours in each corner of the car.
I just tested out my loom and can tell you that the wire closest to the clip is positive.
 
I also found that my Gordini doesn't have any tweeters in the dash, there is just a plastic dummy in there and no wire so the Pioneer replacement component speakers wont work.
 
normally the wire is plugged to the dummy tweeter, if not check if its not just hiding in the hole somewhere, really cant see renault not putting the wires in