This is right at the limit of what my WivaMac DB1200 can take between centers. In order to manage it safely the drives were counter sunk. Not something I'd necassarily recommend, but interesting in so much as it exceeds the spec of the machine and was achieved safely. I reduced the turning speed to 900rpm just to be sure it was all safe.
The reason I didn't get the extension bed out and set it all up was that the client had assured me it was a standard newel - without specifying length, and the quote was based on speed of time to turn. An hour moving the workshop around and setting up the extension would have wiped any benefit from turning it in the first place.
Just thought it might be interesting to some!