Doug, your Salt Cat is totally different by the airflow concept.....
Woody used for the simulation the body shape which I had done as a concept for Sparky...
About a other rear end for the lakester....have no idea in the moment what Sparky got here in his mind...but he will tell me
The current rear end will "close the hole" very well.
Also a idea which Sparky wrote, not too long ago, to give the rear end a little bit more ground clearance, will be a good idea....it will eliminate a airflow interference (hope this is the right translation of the German word)which I can see on the simulation picture, around the rear axle.
There is also a second front end concept with a integrated wing, which would change the airflow picture to the simulation from Woody.
The way how the front end will be at last, is a question, how (airflow) clean will be the front axle.....necessary for the concept is, that the wheels got covers on the out and inside to reduce the air resistance....the highest percentage on the drag at a lakester racer comes from the free turning wheels and the axle which sticks out of the body.
To use a more narrow axle on the rear means not in same time a lower drag....if the airflow can go clean between the rear wheels and the body shape the drag will maybe lower at last.....it all depends on the overall design concept....important is, that the airflow can run along the body shape with the lowest number of "interruption".
The concept I done for Sparky was created to the "possibility" of his workshop.......
Looks a little like the Salt Cat ll
Doug