After reading through a few more threads and contemplating what I need I think that even if I could get the vector data from the model it may not be useful if I cannot properly scale it.
For a typical wall panel (framing) drawing I would probably put it on a Arch C, Arch D or Tabloid paper size and I would probably scale the drawing so that it is 1:24 scale (1/2" = 1’). To make my PDF drawings useful I would like to have them precisely scaled so that when they are printed full size on a printer or plotter they can be utilized in the field by contractors, engineers and architects (ie. you can put your scale on the drawings and pull dimensions from it). Scaled drawings may be a bit old school for some of the younger generation but that is the only way to really make it work. My own kids laugh at me when I espouse the virtues of my engineering and architectural scales but one of these days they will get it.
Perhaps my only and best option is to simply recalculate all of the wall framing geometry (only 2D data, wall depth data not needed) within this module and then use the drawing methods of the PDF generator (prawn) to do the actual vector/line drawing creation and fills. Certainly more work than I want to do right now but I don’t see any other option at this point.
This actually ties together nicely with the DXF export feature I am also considering. For this feature I will also need to essentially regen the wall framing geometry in order to create the appropriate 2D geometry for the DXF file.