angles on driveshaft / u-Joints stock leafsprings with caltracs

Yeah, no way to measure under load or actually measure pinion wrap up that I can think of... but I'm a hack!!! Mines 3* down trans, 2*down pinion at rest with shims...

I snagged some 2* shims and played the install and drive "is it quieter" game... I also tried them in/out at the track to see if I picked up and no change either... but I'm mostly street car, occasional track like you.

Good luck!
Joe