Hi Ron,
I'm sure you'll have a great time... you have terrific timing too, one of your dollars gets you almost two of ours!
Two things I'd recommend,
Go for a bridge walk, you can climb over the Harbour Bridge ( as part of a group ) & book your wife and wourself in for dinner at the revolving restaurant in Centrepoint Tower, I can't remember what the food was like but the views of Sydney at night are beautiful...
Have a great trip!
PS. watch out for drop bears.
