Maybe this is a silly question, but how does the "parkling break setup" on the video units work with a manual transmission car? Is it wired to the hand-brake? Would I need a parking brake override cable like this: http://www.amazon.com/AVH-X1500DVD-AVH-X2500BT-AVH-X3500BHS-AVH-X4500BT-AVH-X5500BHS/dp/B00A9AQPUU/ ?

Thank you!

Parking brake and hand brake are the exact same thing.  Manual transmission vehicles are no different from autotmatic transmission vehicles in the wiring of the brake.  At the brake switch(mostly) there should be a connector with a wire that goes to ground when the brake is engaged.  There are some exceptions to this rule though as far a location of the wire you can use.