One method. Another would be to draw a surface on the YZ plane arrayed along the X axis and converted to a polysurface, create points along the X axis, use a closest point to node and pull the X value from there.
One method. Another would be to draw a surface on the YZ plane arrayed along the X axis and converted to a polysurface, create points along the X axis, use a closest point to node and pull the X value from there.