wondering what the pinion angle should be in relation to the driveshaft
The pinion angle is a function of the tranny output shaft angle.
If the tranny is down 2 degrees, the pinion should be up 2 degrees.

Typical universal joints are designed to operate within 3 degrees of offset.
Any angle beyond that may cause binding.

An angle of 0 will not cause the u-joint needle bearings to rotate as they should upon proper installation.

BTW, Dave started posting back when computers were kerosine-powered.
I'm pretty sure Dave had an Eniac account in 1955.