When lowering the diff to facilitate drive shaft removal and installation lower the sub-frame with the diff. Don't try to remove the diff from the sub-frame.
The sub-frame can swing down about 5 or 6" with out harming the emergency brake cables. The shocks will limit the drop.
Should only take five minutes to undo four bolts and lower the diff on a floor jack. Next time.
Note: If you want to ever remove the diff from the sub-frame lower it first for easy access to the top nuts.

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1984 300SD turbo 126
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