Assemblies, devices, and methods for positioning the same proximate a target site within a body lumen are provided. The assembly includes first and second components that can function independently of one another to address a patients vascular abnormalities or can cooperate to form an assembly. The assembly is designed to address aortic pathologies near clusters of arterial branches in a way that allows blood to continue flowing to the arterial branches during the procedure while providing an adequate landing zone for the adjoining component. One of the components may include a tapered portion near one end that can be received by a corresponding end of the other component. Alternatively, one of the components may include an invaginated end that is able to receive a corresponding end of the other component such that the position of each component is substantially fixed with respect to the other.
