300k fluid in the center diff. So far so good. Excellent traction and still not an uncontrollable wheelie machine.

500k and 1m are on order for further testing. It is great that center diffs with different fluid can be swapped in 2-3 minutes. Allows comparisons within a single session.

Good advice from everyone here - thanks!

Next up is deciding what weight fluid to put in the front and rear diffs. Right now I have the stock weights. I think I will try 80k up front and 50k in the rear.