stupid question: Positive and negative on stock speaker wire

[EastTXYukon]

This is a dumb question, but I want to be sure before I button everything back up. I'm replacing stock speakers in my Yukon. Not doing a system, not running new speaker wire. So which is positive and which is negative for stock speaker wire? I'm working on the passenger front door speaker. I have a light green and a dark green wire, and of course the stock speaker has no indication on it either, except for an A and a B. Please help!

 

[SunlitComet]

light green is plus. dark green is minus.

 

[EastTXYukon]

Thanks sunlit i knew i could count on you!