looking for pinion/yoke angles...

[Eturnit3]

Im trying to find any info on proper way to set pinion angle. Im swapping in a 14bff into a half ton 72 long box on about 4" lift running 350-sm326-205 if its relevent. I need to know:

What surface should my angle finder should be measuring from (the face of the yoke?)?

What should the angle be relative to? the ground? the yoke at the transfer case? the driveline?

Is the slope my truck is resting on, a problem in determining proper pinion angle? What do I need to take into consideration if so?

Is the a General ideal angle?

Thats about all... oh, one more. Its my understanding this measurement is to be taken at ride height? does it matter? (Im getting ready to weld on my perches and I dont want to put too much pressure on whilst unwelded and mocked up, Im not sure if it would hurt anything, but I hate finding out the hard way) Thanks in advance.