Don't know if you're aware, but the easy way out is to ascend the other (eastern) arm of David Crevasse. Brings it down to a half day trip. There is one medium / difficult scramble, shown in the 1990 photo. Back in the 60s and 70s various clubs used to programme a trip down Zoebles and up David. Doesn't seem to be done anymore.
An alternative, if you're really keen, is to head west round the base of the cliffs and ascend the Gordon Smith Chimney (GSC). The GSC was done occasionally up until the early 70s when a rockfall apparently (details are vague) made it a lot harder. Trips since are rare. Any party attempting this should include a competent rockclimber and ideally someone who has been there before as there are a couple of route choices. Our 1993 trip was down Orang Utan and up GSC, which must surely qualify as one of the all time epic day walks.
The GSC can also be done as an abseiling trip (slightly different to the ascent routes). Six abseils, 2x50m ropes. Probably a good idea before attempting an ascent.
Regards,
Graeme