Light green/yellow stripe - Battery (constant pwr)
Yellow/black stripe - Acc (power when turn key)
Orange/black stripe - Day/night Ill.
Red - Ground (Im not positive on this one but pretty sure)
As for the speaker wires I cant help.. but you can use a AA battery to find out. Just touch each end of the battery with the wires - you will get a humming noise out of the speaker they run to.
Good luck
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The battery idea is a good one, I'll have to try that.