After the green button has been removed using the bent screwdriver technique, http://ukvacuumspares.cardpayment.net/_private/misi.htm
take the time to make a mark at the top of the square where the tag of the green button locates into ,remove switch assembly drill a small hole in the grey plastic body. Next time the cable/switch needs to be repaired simply gently push a small screwdiver in the hole to dislocate the tag.
Don Peacock, September 2005