Queensland State Archives posted a photo:
From the Queensland Heritage Register.
The Post Office was constructed in 1886 at a cost of £17,235. Dennis Kellcher submitted a tender and carried out extensions in 1888, while a clock tower was built by Henry L Davis & Co. Chimes were imported from England in 1889 and installed by 1891. As a result of severe bomb damage done to buildings in Darwin, the clocktower was dismantled in 1942 and the mechanism was stored away. A greatly modified tower was built in 1963-64 by JE Allen & Co. of Townsville at a cost of £42,135. The interior was also modernisation at this time. Because of its prominent location, the Post Office often became the scene of political rallies around a speaker on a soap box.
Queensland State Archives Item ID436299, Photographic material