Your pinion is -3 1/4 nose down relative to the engine/trans centerline. What type of rear suspension do you have?

Have you tried rotating your driveline 180 degrees and reinstalling it? Measure the runout of your axle flanges, try a different set of tires/rims and see if it changes?

1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)