Reducing effective size of plug / socket behind dishwasher

[geojay]

This was my eventual solution, using elements from various helpful suggestions above. It needs the plasterboard tidying up but other than that, I think it's a reasonable job. I used 2.5mm² T&E to go to a new box (fixed to the wall behind the plasterboard) on the right wall, running the cable horizontally behind the plasterboard. I joined it to the existing feed using Ideal In-Sure connectors which I hadn't encountered before and seemed to be a great innovation, needing only two hands to connect three cables together rather than the traditional four
The plug in its new location, accessed through a cut-out in the right-hand board is completely out of the way of the dishwasher so mission accomplished!

Thanks for so much valuable advice!

 

[plugwash]

You did put a blank plate on the old box after taking the pictures right?

 

[geojay]

You did put a blank plate on the old box after taking the pictures right?

Where would the fun be in that?

Yes, it's blanked off now...