Pinion angle help.

If your transmission shaft centerline is 1 degree down from level and you set the pinion at 3 down from level that is FOUR DEGREES. Seems to me that's getting a little much. All this has to be measured with loaded weight on suspension, with suspension ride height at normal driving height. This is ALSO somewhat of an estimate depending on your rear springs........factory stockers, cheesy 6 banger, or really beefed. They will twist "more or less."

The two shafts........the transmission shaft centerline........and the pinion shaft are to be PARALLEL under full house power.