Sorry, Iīm still using the yellow friction dampers, so I donīt have any sugestions. In my opinion, damping in a m-type chassis is highly overrated anyway...
I use 50 k diff oil at he momment, but I think the diff ist to stiff, because the car understeers heavily when acclelerating. The diff screws I got together with my repacement diff gear where shorter than the original screws, so I uset those instead.