from the February 2007 RootesReview:
The wiper motor wires are cloth covered and they should be color coded as follows:
NLG = brown with light green
RLG = red with light green
G= green +12v line
I had to look at my wires under a magnifying glass to see the colors. The red was evident but the brown and green were very faint.
I just happened to find a wiper motor in my parts bin and the color of the wires was dingy. I wiped them off with a little foam engine cleaner and the wire colors became clear.