Thanks Jamjar
I received the death cert & is def my William . Dundees lead for arrival of William 1877 on the Samuel Plimsoll ship aged 22,seems to fit perfectly.Died age 66, about 45 years in NSW from County Cork Ireland,groom.
There were 8 children,the first 2 deceased sons William & Thomas 1883were not mentioned.
Catherine Nimmos family were Presbyterian which explains the civil wedding ceremony & their children were raised Catholic.
Now to finding Williams parents in County Cork Thomas & ?
Many thanks for everyone's help.greatly appreciated.