Looking at the photo again the washer wire is green whereas mine is white.

Ahh that makes sense I don't have the single wipe although I have 2
speeds. I think my wiper switch has been apart and put back differently
and/or is a hybrid as the stalk has definately been removed at some time
as the white wire for the washer looks to have been extended and has a
spade terminal join in it. The wiper positions also do not match the
picture on the arm i.e the arm says up for position 1 and then 2 and
down for single wipe whereas the wiper work the other way ie down for
position 1 and then 2. although when reversed to match the stalk by
moving the wires in the switch the arm doesn't quite seam in the correct
position in relation to the hole in the column cowl.

Anyone know the correct colour sequence for the wires and how the spring
 fits.

It makes the stalk return when using the momentary single wipe, but I
believe it also forms the electrical contact for the higher speed in
the wiper motor.

Mine wasn't working so I took it to bits and fixed it but couldn't work
out what the spring did or how it went back, I left it out and the
wipers still all work and park.

The spring is just visible what's if for?

Did you ever get your wiper switch back together properly?

If not, or for futher reference, picture of the correct positioning
here:

http://home.earthlink.net/~michael.walsh/mjw/P2140062.JPG