In a guide assembly for an open-roof system of a vehicle, a closure member selectively covers or at least partly uncovers an opening in a vehicle roof. The assembly comprises a guide extending in a longitudinal direction of the vehicle; a mounting element for mounting the closure member; a first support mechanism operatively coupled to the mounting element, the first support mechanism slidably supporting the mounting element in the guide; and a second support mechanism coupled to the guide and comprising a support element slidably supporting the mounting element, the second support mechanism being configured for moving the mounting element to a tilted position, a tilt direction being substantially perpendicular to the longitudinal direction. The assembly is provided with a release mechanism for releasing the mounting element from at least one of the first support mechanism and the second support mechanism and for remounting the mounting element.