"right now I am struggling to think of another car maker who still uses a rigig driven rear axle. They all seem to have gone irs or front wheel drive or both."
Funny you should mention that, I have a 3 year old, modern vehicle with a solid back axle on cart springs - my Toyota HiLux pickup, Mitsubishi L200 also uses a solid rear axle, and possibly Ford on the Ranger and VW on their new pickup may have a solid back end. It's all a matter of lateral thinking.
Very interesting to see the CAD design Brian and good to know that the factory, aided very much by you, by the sound of it, are thinking about a modern version of an old problem.
