CADWorx Plant I tab: LNum > Line 
Setting toolbar: Line
Plant menu: Utility > Set Component > Line
Command line: COMP2LINE
Sets the current line number by selecting a component with the required line number. Any components created after running this command use the new line number.
This option requires that you set the LineNumberSystem variable to 2. This is the same as selecting the System On (Static Size/Spec) option in the Line Numbering System dialog box. For more information, see Line Numbering System Dialog Box.