I think I got the rear arms for the new car totally figured out. I've been messing around with it and I think they are as perfect as my limited CAD skills can get it.

Front view:




Bottom view:




Outside view:



Inside view, outdrive relief:




Rear view:



Rear bottom view:




Ill show pics of the finished arm once I have it printed out. Then I might put the file on Thingiverse, Ill see how it goes.