When you test the door fit, is the beltline of the door matching the beltline of the cab front and back? The doors are slightly wedge shaped so that by lowering them, you will increase the door gap.
I would check the beltline alignment before a got out the BFH for door opening adjustments.
Carl

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission