VSS on the 2002 Impala

I am building a k-9 police vehicle and cannot find a VSS lead with enough voltage to shut off th bail out circuit when the vehicle is moving. I tried the green lead at pin K of thre cruise, as well as several other points in the car. I can't just hook this circuit up with ignition because the poilce will sit at idle and release the dog from the car. To clarify, there is a remote tstart system to keep the dog cool, and a door release to let the dog out one door. it unlocks then releases the door and a strut pushes the door open. I do not want the door to open when the vehicle is moving. This could injur a very expensive dog.

if you have a 3.1 or 3.4 sfi engine check plug on trans. passenger side the color is yellow and blue. this is the vss  lift the car is easy to view  plug

Does this help Philo  ??:

02  CHEVROLET  IMPALA 

http://www.rostra.com/pdf/wirelocations.pdf