First you need to check the angles to see if it needs to be adjusted. With the rear suspension at ride height put an angle finder on a flat spot of the yoke coming out of the trans. Then put the angle finder on a flat machined spot on the rear axle pinion yoke. The trans should be down and the axle up and close within a degree of so usually. But the axle should not be up more than the trans is down. So if the axle is 2 degrees positive and the trans is 3 degrees negative that's in the ballpark. If you have large rubber bushings and a big engine you can go with say 1 degree positive (up) on the axle or sometimes a greater difference because the soft rubber arm bushings and the torque will cause the axle pinion to rotate up. When it rotates up it should be close to the down angle of the trans but not exceed it. Hope this helps.
