Basically, your auto PCM doesn't have the ability to run a hall effect type sensor.
The autos run a 2 wire sine-wave sensor, these pretty much just open and close the circuit and the PCM registers it. (Getrag manuals are also like this)
A T5 is a 3 wire hall effect and sends a square wave 5v pulse up 1 wire to the dash/ PCM. It has a 12v ign feed and an earth.
The VT L67 PCM can be programmed to use a previously unused pin as a hall effect input, i dont know if the VS PCM is the same.
Its not just plug and play, the tune has to be modified to suit the amount of pulses per km the sensor gives off. Mine is straight from sensor to PCM but i believe factory T5 car runs the sensor wire to the dash then its sends a signal to the PCM. I dont remember which pin we used exactly, but its not on any diagrams anywhere, my tuner found out it was possible.
There is a lot of small idle problems in relation to the speed sensor, it will need to be properly tuned or it will be annoying to drive. You can temporarily not give the PCM a speed signal, it will run fine without it.
With your speedo, from memory you just connect the brown wire from the sensor to the clusters speed signal input wire but you would have to check a wiring diagram to be sure.
