Help with D8T diffs

[FormulaZR]

This is an old thread...but exactly applies to my question.

I have a pair of RC-M converted D8Ts. When they were nitro, they performed very well with 5/7/3 diff oil at my local track. Now they are brushless, and I assume they'll need a change. One is powered by a T8 2000kv running 4s and the other is a T8 1350kv running 6s. Both are using RX8 Gen2's in sensored mode. Both are used as racers only, no bashing - the track surface is fairly loose and has quite a few tight turns. The longest straight is 150' or so.

Any ideas on where to start? 10/10/5, 7/10/5? Or...am I way off on center diff wt?