How exactly do you measure pinion angle of the TA? A degree or two either way seems like an extremely tight tolerance!

 

When I did my LT1 swap, I placed a degree measuring tool w/ a level on top of the intake, and did the same to the top of the differential yoke. I think as long as they're as close as possible it should be good. Some people suggest even setting the rearend a little off for it to be aligned when under a certain load. You don't want it straight though.

 

It's been a while but if I remember correctly you take your magnetic angle finder and you put it on the flat part where the TA
mounts. Then you take the angle finder and put it on the drive shaft. You then that amount of angle from the drive shaft and minus the amount from the reading that was taken from the TA mount. That number should be your pinion angle.
Hope that helps.
Later Colin

 

Here's a writeup: http://www.go-fast.org/z28/pinionangle.html

Dave

 

Thanks Dave that is a better writeup with some pics.
Colin