It's quite difficult to ascertain the exact point where Brady (Mark McGann) is simply because the area doesn't have too many identifiable landmarks, however, the following picture gives us a slight clue because it contains some of the buildings that can still be found on the nearby Tung Tau Industrial Estate. The building to the left of Brady is the Hung Wai Industrial Building. If you look closely it seems to be empty, this could be because it was newly built in 1988 (I'm still unsure if the filming of this series occurred in 1989 or 1990).
The next shot shows us a wider angle of the same direction with a nearer building partially obscured by the panel at the end of the wooden platform. This building is also still around and sits on the northern limit of the industrial estate. It's the Mansfield Industrial Centre, also completed 1988 which makes me think 1988 was perhaps the year when the estate was itself finally up and running.