For a 2005 Ford Crown Victoria, you would need a 94012-0002 and a 5556 installation kit for driver side mount. For passenger side 94013-0002 and a 5557 installation kit would be needed.
94012-0002 was not commonly used in police applications. If you are going for authenticity, 94014-0002 spotlight would be used instead for driver side. 94015-0002 for passenger side. Same installation kits would be required 5556 Driver, 5557 Passenger.