Which way should I go with pinion angle ??????????????????????

Set it at 4 degrees down from the shaft, so when it is under power it is at 0.0

put the housing in the car slightly tighten the u-bolts, put it on a drive on lift, 4 ramps, whatever and then adjust it to the 4 degrees down from the shaft, tack the percehes and then weld them, then check the housing is still straight and hasn't moved, which they usually do.
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