Vale of Leithen0
Vale were powerless to prevent the East Kilbride onslaught, with Joao Victoria scoring an opener in the 11th minute.
The Portuguese striker fired a second home on the half-hour mark and the lively Liam Gormley netted a third as half time approached.
Vale tightened up after the break, withstanding more attacking play by the hosts and keeping possession well at times. But while this result saw East Kilbride take over top spot, it also saw Vale sink to the bottom.