This was a pretty straightforward problem if you know how to use the API Help. In the local API Help, I searched for "component line font" and it became apparently quickly that all of these settings were controlled in IDrawingComponent. In particular, IDrawingComponent::SetLineStyle does what you need. The second argument is where you specify the style you want. I am not certain I am using the one you want. If not, look at swLineStyles_e and find the one you want.
If you want to learn how to use the API Help, check out some of the video tutorials at my web site.
Dim swApp As SldWorks.SldWorks Dim swModel As SldWorks.ModelDoc2 Dim swSelMgr As SldWorks.SelectionMgr Dim swView As SldWorks.View Dim swDrawComp As SldWorks.DrawingComponent Sub main() Set swApp = Application.SldWorks Set swModel = swApp.ActiveDoc Set swSelMgr = swModel.SelectionManager Set swView = swSelMgr.GetSelectedObjectsDrawingView2(1, -1) Set swDrawComp = swView.RootDrawingComponent swDrawComp.UseDocumentDefaults = False swDrawComp.SetLineStyle swDrawingComponentLineFontVisible, swLineHIDDEN End Sub