headlight washer question: plumbing the 2nd tank

[Paul in NZ]

Bentley is pretty thin on all aspects of headlight/intensive wash system.I wonder if the stealer can help,cos i note in the etk that these can be installed retrospectively as a kit,maybe there are bulletins or something in the tis??
I hope the hoses for the headlight washers are in the bumper cause i am pretty sure thats where they run,and the intensive clean fluid hoses hook into them too i think via valvesMy understanding of the sytem is that when you do the intensive clean the headlights get a blast of fluid otherwise they get washed every fifth windscreen wash

OK, so I need to nix connnecting the two tanks together. That makes more sense. I didn't realize that the fluids would be different.

Does the bentley have anything on this installation?