Didn't change the diff. Had the car out one time , so far.
3k RPM at 60 MPH / 100 KPH.
New shifter works VERY well ! Sits so far to the left I used the small white ball. Just changed it out with a T handle , with the line lock button.
So I'll have to keep my right leg straight up.
New (to me) 15 x 3.5 wheels leak. I have to take the off & water test to see what is leaking....