To Create the Equivalent of an Overlay

Open the References dialog ( Drawing > Attach > References dialog launcher ).
In the References dialog, click the Attach Reference icon in the tool bar.
The Attach Reference dialog opens.
Select the desired file to overlay on the current file, then click Open.
In the Reference Attachment Properties dialog, click on the Options button.
In the Attachment Properties dialog, turn on Ignore Attachment When Live Nesting, then click OK.
Enter the remaining reference settings, then click OK.
Note: If this drawing file is attached to another file as a reference and thus becomes a child rather than a parent file, the overlay will not be displayed.