Hi,
1. Edit the view "checkout / address_view" and change the sizes in the code: {handler: 'iframe', size: {x: 450, y: 480}}
2. Edit the view "address / listing" and change the sizes in the code: 760, 480, '', '', 'link'
3. Edit the view "order / show" and change the sizes in the code: 760, 480, '', '', 'link'
To find the view which is calling the iFrame, you have to know in which view you currently are.
When you are seeing the addresses, so it's the address / listing view, if you see only one address and you are in the checkout, so it's an checkout / address view, etc.