Well, I started it.  This was an obvious choice for conversion to a wagon.  Somewhere in the bowels of my modeling room, I have the box with the various pieces, side views blown up (down) to scale and brass roof that wasn’t working out the way I wanted.  Then I learned that R&R Vacuum Craft was doing one in resin.  My project went on hold.  Still looking (but not too hard anymore) for the R&R body shown.