[nlped]

You need an angle finder to set the pinion angle to the correct angle. I bought one at Lowes in the tool "barn". It's magnetic, so I just stuck it to the pinion flange and put the rearend and new perches in place and rotated it until is was at 3 degrees which is what the stock angle was at and spot welded the perches then pulled it back apart and welded everything up. O BTW, made sure the truck was level left to right and front to back to confirm the angle was correct across the board.