driveshaft angles

View attachment 1716046775

This is what it should look like. The angle isn't hugely important, but they need to be equal and parallel as shown.

The rear might twist up 1-2 degrees at cruise too, so slightly nose down at rest is OK, but it can't "break across zero" (meaning the angle between the shaft and the pinion cannot go across 0 degrees, or -1 to +2 for example), and you never want the pinion and driveshaft in a straight line either.
While I agree in theory with that graphic, it's wrong, wrong, WRONG for any type of performance application. The Mopar Performance manual has the dead best explanations and graphics for both street and race.