[Maxo]

After further investigation I've concluded that the loud clang is not my rear diff, it's the drive shaft.
When I swapped my transmission I also packed the rear differential bushing and the transmission mount with urethane. The added rigidity really amplified an existing problem with the front u-joint in the drive shaft.
The clang had me convinced that the issue was in the rear of the car but after crawling underneath and checking things out it became quite clear where the noise was originating.

The drive shaft u-joint doesn't even seem that bad, it sure does make a lot of noise though.

So what the consensus on what to do with a bad drive shaft? repair/buy new/buy used/buy rebuilt?