John wrote:
I have just fitted a double MK dimmer in place of a normal 2 gang
switch.

It is a bit tight and I fear that the heat may cause problems as the
wires are all crushed a bit.

Is there a spacer available that will bring the switch plate forward
by about 5mm to give more space?

Having just decorated I don't want to change the box.

My MK dimmer came with exactly one of those.

Was only a single though, and only about 3mm.