To Attach a Reference Coincident

Click the Attach Reference icon ( Drawing > Attach > Reference ).
In the Attach Reference dialog, select the DGN file that contains the model to attach as a reference.
From the Attachment Method option menu, select Interactive, then click Open.
The Reference Attachment Settings dialog opens.
In the Reference Attachment Settings dialog, select the model to attach.
Do one of the following:

To align the reference with the active model with regard to both Global Origin and design plane coordinates, select Coincident - World in the Orientation list box. This option is available only when referencing a model in a DGN file.

or
To align the reference with regard to design plane coordinates only, select Coincident in the Orientation list box.
Modify the other attachment settings as needed, and click OK.