CADWorx Plant tab: Dimensions > Elevation 
Plant menu: Text > Annotate > Elevation
Command line: ANOTELEV
Places component elevation annotation.
Options
BOP
Labels the bottom of the pipe elevation.
TOP
Labels the top of the pipe elevation.
Centerline
Labels the centerline elevation.
Justify
Allows five different justifications according to the CAD standards. For more information please refer to the CAD documentation.
Leader
Adds a leader to the text.
Start point
Specifies the starting point for the text.