When placing a balloon including the item number in a draft from an assembly,
the balloon does not show the item number but 'NA' instead.
If you want to extract an item number linked to a Parts List, the Parts List
has to be active. Under normal circumstances the last placed Parts List is
active. If it is not active, you can make the Parts List active as follows:
Right-mouse-click on the Parts List and select 'make active'. Having done that
you will be able to place balloons including the item numbers.
Notes and References
OS Version: 764SP1