The a-b-c-d rectangle is used as an initial YZ plan with point b as the origin. Input data for inserting the origin of this plane are shown in Figure 107

Figure 107

This window shows the section by adding segments. The list of segments is given.

Figure 108

The extrusion plane will be e-f-d-c (see Figure 103). The coordinates of three nodes are required to define this plane. Any combination of three points can be used in this case. However, the extrusion height will not be the same for each node. In this figure, the f-c-d nodes were used to define the extrusion plan. 

Figure 109