[Chunka]

Thanks Citroenbender,
I carried that out today, that is removing the wipers, scuttle, glovebox, cabin filter. And cleaned it.
My next goal is to get access to the evaporator coils so I can apply a detergent foam to clean them via an application tube. One option is to come in from the front under the windscreen into the vent. This brings the tube to the top of the blower rotor. A question. Is the blower waterproof from rain etc coming from the outside vents? Surely it must be?

I am trying to avoid getting underneath, finding the ac evaporator drain hole and having to insert the tube into it.