Thanks for your input. I think Rustednuts is on target. Just hope there is room for bolts. Swampcat, swapping out the diff was my first idea. I have a complete 41 setting out in the parts pile. However, 1939 (37-39) is a bit of a different animal. Anything from 40 up uses a different propeller shaft/tongue tube. I could probably work around this but in 40, when they started bolting on the ring gear; everything got shifted ½”. This is reflected in the left axle being shorter than the right. My axles are both the same length. This means that the opening in the housing is centered in my diff and ½” offset in 40 and above. This limits my replacement possibilities to 39 (possibly 37-39) or maybe a complete 40 assembly axles and all (¾ ton only). BTW, mine is a ¾ ton. About the same as ½ ton in 39 with the addition of an extra short propeller/torque tube. It would be great if I could stumble across one within driving distance but what are the odds.