Ok, so I did say it correctly in the how-to. I guess I would have received several 'you are an idiot' messages to the how-to if it had been typed wrong all this time.
crush washer it may not mater but when you replace the crush washer it is less stressfull on the threads of the engine case . the soft copper ring "crushes "and seals after repeted crushings the seal is hard and starts to pull on the threads . only see it as a problem when the bikes are old.