I have never messed with the closed drivelines except for one my dad and I shortened when I was in high school. I do believe that pumpkin can be changed but not sure. The way the axle mounts on the springs is sort of hinge that allows it to move with the ball connection at the tranny end. I think that would not work with two U-jounts. But again I'm not sure. It is a pretty easy fix to weld new mounts on the axle housing. The oldest rear end I have here is a '49. I also have what I think is an early open drive line rear end. I'll try to check them out. You might have some luck on the Stovebolt site.
