This particular early design not only had sewn flutes on the Fleck material, but is different to later to later models in that the sides of the cover extended down into the rear wheel arch pocket. This also means that the rear metal wheel arch itself does not have a vinyl cover as per later cars.
The special horse hair pad is actually glued to a metal bar that sits on the rear parcel shelf. The seat cover is then laid over this unit, the top skirt is glued to the back of the metal bar, then the skirts on the cover are turned over the horse hair pad and glued in place.
Newton Commercial Part No - SC3108