I'm about to get off work in 45 minutes and head to the house to install these Kappa door speakers in my rear doors. When I unplug the stock speaker, which I'm almost certain it has a connector, how do I tell which is the +/- wire to hook into my crossover?

 

Here ya go, this is also easily found with a quick Google search, i copy and pasted it on here.
Ford F150 Truck Car Radio Stereo Wiring Diagram

Car Radio Battery Constant 12v+ Wire: Light Green/Violet
Car Radio Accessory Switched 12v+ Wire: Light Green/Yellow
Car Radio Ground Wire: Black
Car Radio Illumination Wire:
Light Blue/Red
Car Stereo Dimmer Wire: N/A
Car Stereo AntennaTrigger: N/A
Car Stereo Amp Trigger Wire: N/A Car Stereo Amplifier Location: N/A Car Audio Front Speakers Size: N/A Car Audio Front Speakers Location: N/A
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: N/A
Car Audio Rear Speakers Location: N/A Left Rear Speaker Positive Wire (+): Gray/Light Blue
Left Rear Speaker Negative Wire (-): Tan/Yellow
Right Rear Speaker Positive Wire (+): Orange/Red
Right Rear Speaker Negative Wire (-): Brown/Pink