When I did mine I put the angle finder on the yoke. The idea is to get the angle finder flat with the yoke.
Now what type of driveline do you have? CV or Non-CV?
CV = point the yoke straight at the Xfercase yoke
Non-CV = Measure the Xfercase yoke angle and set pinion yoke angle within 3deg.
Yes you want the weight of the truck on the axel so your springs are pressured by the weight.
I run a CV type rear and I set my yoke 2-3deg down from straight at it, so when my 454 sends all that power to the rear and the yoke starts to stand up...well it was a theroy of mine to equalize axel wrap
