Do you have access to a pneumatic hammer drill? They are quite cheap these days if bought from Lidl or similar. The socket spanner will have to be a slim one.
You could try a small cutting disc to carefully cut axially down the nut without reaching the threads. With one flat greatly reduced the thinned flat will split open when you apply a spanner. You can then inspect the threads and decide whether to clean them up or replace the posts.
I don't have C6 washers for #323 and need to know the dimensions of these C6 washer to assess whether I need them.
Anyone have such information on C6 washers please?
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