Alfredo Morelos hit a hat-trick as Steven Gerrard's team thrashed St Joseph's 6-0 at Ibrox for a 10-0 aggregate success and they will now play Progres Niederkorn.
Aberdeen came from behind to beat RoPS 2-1 in Finland (4-2 on aggregate) to set up a clash with Georgian outfit Chikhura Sachkhere.
Killie went down 2-0 at home to Connah's Quay Nomads after winning the first leg 2-1 in Rhyl last week.