NOW THIS IS CRITICAL and difficult...: To get it right (refitting that huge washer back on, that is) it needs a lot of patience...: The trick is to make 100% sure that the washer is absolutely centred when it touches the "core". And this is very difficult, because the core is about 5mm below the top surface of the rubber. In preparation I took the assy above the other way round (without the washer) and pressed carefully until everything was a bit neater together. Then as you see it above, pressa