On Friday, December 05, 2008 9:29 PM Brian wrote ...There was a scissors
crossover inside the tunnel, and I recall that trams did depart Wynyard
platforms on the southbound line but switched to the correct side at the
scissors.....

Not quite correct.

Most crossovers at Sydney tram termini were scissors type but the tram
crossovers in the tunnel at Wynyard were tandem crossovers (i.e. separate
from one another) They were electro pneumatic in operation from a small
signal box set into the western tunnel wall. These crossovers, unusually for
tramways, had facing point locks which were also electro pneumatic in
operation.

Generally, the tunnel crossovers were only used during peak hours as a
facing crossover from Platform ! (inward track) to Platform 2 (outward
track0 was built through the southern end of the platform to allow trams to
shunt during off peak times. The stub tunnels at this end could accommodate
several trams. The tunnel beyond Platform ! was the usual stabling location
of ballast motor / line car No 99u which was used for overhead wire
maintenance across the Sydney Harbour Bridge.

Noel Reed.