I too have a turbo, car going ok except for rear diff coming apart each run. I've changed diffs with the same issue. I have heard someone say to put the front diff housing in the rear is this true?
Note to help stop the rear end stepping out I've put a heavier front spring (orange) on and have the fr ride height 1mm higher than the rear and this is on a dry dusty track worth a try.
Any sign of Lycan?