Hi,
I'm hoping to get the benefit of your experience.
My wall units on one side have to be deep to accommodate a combi boiler, meaning they protrude 420mm from the wall. The existing worktop is also quite deep (720mm from the wall), which may have been designed either to accomodate pipes at the back or to take account of the deeper wall units above.
Because it is already a narrow kitchen, my original idea ...

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