I still don't like messing around with tubes although this was eight years long my job.
Anyway, unfortunately I'll have to do this again for my rotating monitor-mount, the damn chassis has to much width to fit so I've to bold the tube seperate from the chassis.
But with a clear head and careful hands this can all be done. Always be careful that the tube don't slips out of your hands, the neck is easy breaking! It won't implode if it breaks on the end though, but your $$$ are gone!