After some head scratching and discussion on Railpage – one of the internet discussion groups Australian modellers regularly use to nut things out I have begun.
Progress is at a measured pace largely due to the need to Araldite the brass to the underlying plastic frame. Tonight I have added the headstocks using “Slow Zap” CA which is a slower acting cousin of the dangerous “Zap a Gap” which could be relied to stick anything just where you don’t want it (such as another finger).
The headstocks needed some serious holding in place but there was no space to clamp so CA was the way to go and it seems to have worked.