I don't think it's fair to say that I have 'frowned upon' anything.Well, yes, obviously any method suitable for buried hidden joints may be used - unless 'safe' zones disappear with the accessory, but suggesting anything other than the OP originally stated seems to be frowned upon.
I merely pointed out that since the OP's stated aim was to achieve a situation in which "...the area above the work top has less switches/sockets on display", it seemed unlikely that he would want to go with the suggestion of changing the SFCUs to sockets.
Kind Regards, John