Ducati Diavel Workshop Manual page 646

Cooling system: water radiators
Insert the spacers with collar (2) onto the "upper" vibration dampers (3).
Fix the right coolant radiator (13) by starting the screws (12).
Position the right fan assembly (18) on the right coolant radiator (13), so that the holes in the assembly (18) match the
protrusions (L) on the radiator (13).