How to find out the radio wiring harness color codes on a 1997 mercury cougar

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1997 Mercury Cougar Car Audio Wiring Diagram

Car Radio Battery Constant 12v+ Wire: Black/Orange
Car Radio Accessory Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Light Green
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: Dark Blue
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: 5′ x 7′
Car Audio Front Speakers Location: Doors
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Light Blue/White
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Car Audio Rear Speakers Size: 5′ x 7′
Car Audio Rear Speakers Location: Side Panels
Left Rear Speaker Positive Wire (+): Pink/Light Green
Left Rear Speaker Negative Wire (-): Tan/Yellow
Right Rear Speaker Positive Wire (+): Pink/Light Blue
Right Rear Speaker Negative Wire (-): Brown/Pink