Success! After all this it turns out the pan was deformed under #1. I looked at it when I first took it apart but didn't notice anything. This time there is a slight wear mark maybe 3/16 long. Before taking the pan all the way off, I put in 3 longer bolts so the pan would hang down further. Started it up and NO knocking. I fixed pan so am now moving forward again. Thanks to all who have chimed in here to help.
Dennis
