I thought I had my pinion angle adjusted pretty well Sunday when I attached
the driveshaft, but I have a vibration that starts at about 40mph, dies off
at around 50 and picks up again at about 60.

My helper and I held a carpenters square (the big L shaped one) on the diff
and lined it up that way, pointing directly at the output of the
transfercase... Can anyone give tips that will get me dead on?
n.