Wording can get misunderstood, but this exaggerated representation should help. Looking from the side with the trans on the left, the driveshaft is usually at a "down angle" from the trans to the rear and then the pinion would be angling up - relative to the driveshaft.
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When talking about "pinion angle", it is the angle at the bottom, between the pinion on the right and the driveshaft on left (represented by the downward slashes). The angle difference between the trans output shaft and driveshaft is not used in pinion angle computations. But adjusting the pinion angle can slightly alter the trans-to-driveshaft angle.
Hope this makes sense. It's past my bedtime! lol
Gosh darn, heck. Couldn't get the lines and slashes to stay where they need to be.
