1. Highlight the provided current curve and Lock it...
2. Draw a freeform curve profile similar to the one shown in the illustration below.
3. Click cplane origin
4. Using snap to endpoint click the endpoint on the
curve to set the cplane
5. Copy the the Commandscript below...
6. Highlight the perspective view
7. Run the commandscript by clicking the run command script icon. You end up with a surface similar to the figure below
8. Select all and delete the freeform shape and its
9. Make sure you Reset your cplane back to world origin top
10. Unlock the provided curve profile