Is it 2D axisymmetric (like a pipe) or another type of 2D? If it is axisymmetric, create a surface body that has the axis of symmetry along the X-axis. The radial slice must be on the +Y side of the X-axis. If it is another type of 2D then you don't need to worry about aligning with an X-axis.
If you have a surface body on the XY plane, use SpaceClaim to open the SolidWorks file. You should see a Surface body in the Outline tree. Follow the directions in my first post.
Please reply with an inserted image of the geometry if it doesn't work and you need more help.