...to prevent the housing from deforming. Mercedes engineers plain forgot it.
If a tab is welded across the top of the right end arrangement to prevent it from deforming, it should solve the problem by keeping the adjusting nut straight, and preventing the bolt from deforming. It should take three good tack welds. TIG would look better.
There isn't a lot to prevent deforming with the original design. From what I observed, the arrangement, although appearing to be sturdy enough, seems to have metal that serves no purpose, with the end result being only as strong as one that had only one tab.
Once this is welded, the weak link in the assembly would be the adjuster threads. or perhaps the fused bolt joint. Don't go using a cheater.
I have a '79 240D with a shiny new bracket. So far, still charging and no squealing. But that may change.

snapped_bolt

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'81 240D For now, a good place to borrow new parts
'80 300TD Probably will be put back into service!
'79 240D BACK IN SERVICE SINCE 09/16; limited use, oil leak. Guide pin r/sealed/replaced. Still a leak. Front crank seal....