To Delete an Entry From a Surface Texture Symbol Preset Value List (AutoCAD Mechanical Toolset)

At the Command prompt, enter AMOPTIONS.
In the Options dialog box, click the AM:Standards tab.
In the Standard Elements list, double-click the Surface Texture symbol.
In the Surface Texture Settings dialog box, click Edit List corresponding to the preset value list you want to edit.
In the Standard values drop-down list, select the type of value to add.
In the Preset value list, select the entry to delete.
Click Delete.
Click OK until all dialog boxes close.