I activated the Edit GDL Library Parts Toolbar.
Then I used the Open Object by Subtype command.
From the list of Subtypes I opened the General GDL Object\Documentation Element\Drawing Symbol\Marker\Section-Elevation Marker\Elevation Marker\Built-in Elevation Marker subtype.
There I can see that the Marker displays the value of the
AC_MarkerText_1 parameter.
You should create your custom Elevation Marker by saving one of these default Markers under a new name a modifying it. That way you can use the same parameters and may reuse some of the scripts already available in them.
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