Positioning of the existing parts is one of the last steps before final detailing of the 3D model for generating workshop drawings. ProSteel can do this automatically for you. It searches for parts of the same type and defines their number in the model. Of course, you can also assign position numbers manually.
This Wiki will guide you on how to process numbering of the parts and assign Position Numbers automatically.
1) Once you are done with modelling your structure, initiate the Positioning tool and navigate to the Steel Positioning tab
2) Here, first reset all the values to start by click on the Reset Position Numbers button marked as  in the above picture
3) Now, click on the Process Automatic Positioning marked as  in the picture from Step-1
4) Select the parts for which you want to assign the Position Numbers automatically. You can do this by using the Choose All button to position the entire model, use the filter button to select specific parts or even use the selection tool for picking the parts
5) The application will then process and display the Positioning Results for Single Parts. After reviewing, click the OK / Accept button
6) Followed by this, the Positioning results for Sub groups and Groups are displayed
7) The Position Numbers for these parts can then be reviewed in the Part Properties
This is how one can assign Position Numbers automatically to the steel objects in your model