Dunlop's House was on the north side of Hunter St half way from Marsden St to the church gates.
He catalogued 629 clusters and nebulae and 253 double stars from his backyard in 1826.
http://binged.it/Rlffxw
Here is a picture of his house
https://picasaweb.google.com/1100488...29705361888370
latitude -33.816 longitude 151.002
It seems to be lot 27 in this dig
http://www.higginbotham.com.au/pdf/Marsden01.pdf