pinion angle

If your a heavy guy throw weights in the car to match.
Measure 4 points around the car, bumpers will do.
get the car up at a working height, jack stands under axle.
Do the math, bring up front of car to mock height sitting on the ground.
Check the degree at the tailshaft down angle, pull rear pinion up the same degrees, with maybe 1 deg. down for axle wrap up at cruise.
JMO