Distance between sockets and fcu's in Kitchen?

[Tasty]

Hi,I'm just mounting 3 back boxes for 3 seperate functions above a kitchen surface, one double socket, one cooker switch and one 2 gang control switch for the fridge and under cupboard lights. I was just wondering if there is a min distance to observe between these? I'm most concerned about the plasterers actually as they're using 50mm sound proof board so I dont want to leave awkward 20mm gaps for them to fill (or am I being too nice?) ;DSounds like a simple question but I can't remember if there is a distance between sockets to be observed!?Cheers for any replies!

 

[pennywise]

I use 20mm metal conduit couplers and brass bushes.
Two between each box, keeps the boxes in line.

I do exactly the same thing, comes out perfect every time. I find those all in one boxes a real ball ache sometimes when using decorative plates, some manufacturers make their plates slightly wider outside of the lugs and it can be a bit of a wrestling match.