BLACK - EARTH
RED - CONNECT TO PERMANENT POSITIVE FROM BACK OF IGNITION SWITCH
Remove wire from ignition switch (Position 2 - I.E normal running position)
and connect the wire removed to YELLOW WIRE.
Connect SMALL grey wire to position 2 ignition switch where original wire was.
Connect BLUE wire to position 1 key switch connection along with existing original car wires.
Hope that helps - Best educated guess for want of better words
If this doesnt work (try swapping YELLOW and BLUE wires)
(You wont damage car or unit if wrong)