Rear Wiper/Washer Switch - which wires????

I've got a wiring query but can't seem to find a decent wiring diagram on the net and I'm awaiting delivery of a Haynes manual. Hope someone can advise.
Rear wiper has never worked since we bought our 90 so I thought I'd check it out today. Took out the small panel holding the ciggy lighter and rear wiper/washer switch only to find no wires connected to the wiper/washer switch. There are a few wires/female connectors sat loose on the dash. I've got a

• Single Brown
• Single Red/Light Green
• 2 x Black & Green; and
• 2 x Green

There are three male connectors on the wiper switch. One of these has got a Black (earth???) wire connected to green coloured block at the centre of the rear of the switch. Don't want to experiment as it seems the wrong time of year for fireworks!
Please can anyone advise which wire goes where on the switch? I've got a pic of switch if needed, but it is a standard switch
Cheers.

According to Haynes you should have a red/light green, Brown/light green and a Green wire to the motor. And a Light green/black to the washer pump.

Thanks Grunt. Looks like I've got to find a Brown/light green one in there somewhere.
So, if I do find one, that'll be four wires but only three male connectors on the back of the switch.
Any ideas what goes where?

GRUNT said:

According to Haynes you should have a red/light green, Brown/light green and a Green wire to the motor. And a Light green/black to the washer pump.

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