Oh...pinion angle question...never fear they will be plenty of answers.
How did you arrive at those numbers you posted...
I assume the proper way to set pinion angle is measure the transmission slip yoke then measure the rear end drive shaft yoke..These are the numbers you want to go by. Make sure the car is level like it would set in the staging lanes or on the line. Its simple math from there. Like +2.5 slip yoke + -4.5 pinion yoke = a -2 pinion angle.
Cause of pinion wrap on a leaf spring car most look for 4-5 deg nose down (- pinion angle). Were a ladder bar car or 4 link moves very little so they can read much closer to zero. Any positive pinion angle is bad.