An assembly comprises a housing, a motor within the housing, and a thrust tube with an anti-rotation mechanism. The motor comprises a hollow rotor. An externally threaded screw shaft is coupled to the hollow rotor for rotation therewith. An internally threaded nut is coupled to the externally threaded screw shaft, wherein rotation of the screw shaft causes the nut to move axially. The thrust tube is operably connected with the nut, and the anti-rotation mechanism is attached to the thrust tube to substantially prevent rotation relative the housing.