It takes you to the header page OK, then you have to use the live 'Headquarters' link, to work your way down to 'Divisions', then 1/2 way down the Div list is 1st Aust Armoured.
The new system takes some getting used to, but it is worth it. This must be the only museum in the world to put so many war diaries on line and accessible for no charge. The cost of doing and maintaining that was very high.
The diaries are a wealth of information, but you have to spend the time working your way through all sorts of less exciting stuff to find gems like Shane has informed you about.
Mike C