Ventilation fan

From memory you don't have to remove the dash to get at the ventilation fan but it is a good idea to remove the drivers seat for easier access. Best to drain the radiator first, AFAIR the heater matrix comes out with the fan. Even so be prepared to catch some water when you undo the heater hose. The impeller is usually frozen/rusted solid on the shaft. It is a good time to oil the shaft bearings with a drop of fully synthetic oil, the thicker engine lube grades seem to last longer than