300TDi thermostat fitting & bleeding

Going to stick in a new thermostat today in prep for the winter, will also replace the bleed screws with brass replacements...

Is there any tricks to changing a thermostat and a correct procedure to bleed the water system?

Friends have been telling me different ways to bleed the air/not airlock the system so I wanted to know the correct way to do it for this vehicle.

Thanks muchly

thermostt is prety straight forward just a metter of making sure rubber seal sits in recess and tightening bolts equally not one the the other ,bleeding is simple heater set hot ,undo both bungs fill system till rad flows clear ,fit bung and fill till thermostat housing runs clear leave expansion tank full and run engine ,level in tank will drop as heater etc are fully filled ,recheck level any excess in tank will come out harmlessly till reaches optimum level ,frequently check thermostat bung level as expansion tank can still be correct while air in top of head

Top man, thanks James!

Will get onto it this afternoon