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As long as the pinion and output shaft centerlines are parallel and there's approx 2-3 degree angle in relation to the driveshaft, it's good.

Oh OK you want the centerlines parallel but not in the same plane like the pic AND AT THAT POINT the pinion 2-3 deg downward from the DRIVESHAFT. Cause the pinion will rise up making the pinion & the driveshaft closer to a straight line?

Right, when the car is on the ground and sitting with weight on the suspension, you want the rear and trans parallel but NOT on the same plane (in line) with each other. The 2-3 degree angle is in relation to the drive shaft only not to the ground. As the suspension goes up and down in normal driving, the angle will naturally change a little to the positive and negative to that angle. Most production cars have the engine in the car at a 2-3 degree angle (tail down) in relation to the level plane of the car (and ground). That's why intake manifolds are higher in the back than the front...to level the carb. Then the rear is angled 3 degrees UP to match the engine angle. In theory, the drive shaft (if installed level) will have a 3 degree angle in relation to the rear and trans on each end.

The upper right diagram is described as for tube chassis drag cars only. That will produce the least resistance. Some drag racers with leaf springs will set it up so the rear is angled down relative to the trans, so that under acceleration when the pinion climbs the ring gear, it will then have the correct agle. Then at the end of the race it will revert back to the non-aligned angle. But you wouldn't want that for the street. You will get a lot of vibration and there will be a lot of stress on the u-joints.