Hello rwthomas1
Your decision.
At idle the suction - vacuum is small.
At full boost the suction - vacuum is high.
The turbulence caused by turbo spooling up is amazing.
The OEM air cleaner housing is large and well vented, it does not see vacuum, only slightly reduced air pressure.
The U tube is a tightly restricted turbulent air flow tunnel seeing direct vacuum at high boost.
The crank case is pressurized oil vapor = establishing flow to the separator, the heavy particles of oil swirl and merge into drops which return to the oil pan, it is amazingly well designed and effective.
Ask anyone on the diesel forum who had the separator drain tube become dislodged from the separator, how long did it take for your engine bay to become an oil soaked mess, the answer will shock you.

Last try to make clear:
Pressurized crank case establishes flow to your altered U tube, high boost vacuum occurs increasing draw from crank case, a couple of marginal exhaust valve guide/seals fail, adding more pressure and turbulence to valve spring area oil = sudden increased oil vapor flow into U tube and combustion chamber.
IF you are lucky, the first sign of trouble will be when the engine refuses to shut down, if you are not lucky, when you ease off the accelerator the engine will continue to accelerate to destruction.

With the OEM separator in place, you should have excess smoke and some warning, without it, all the oil blows directly into the combustion chamber and becomes unregulated fuel.

I have skill, ability and years of experience in my field, but NEVER will I claim to be able to predict when piston rings or valve guides/seals may fail.

Explanation of the lame "different designs" answer as to why your other diesels haven't had widespread problems, 1989' Volkswagen Jetta 1.6 N/A and 1993' Chevrolet C2500HD ExCab 6.5TD, these vehicles are next generation design and can not be compared with 1985 and earlier Mercedes Benz, that is the best I can explain without you taking 4700+ hours of design/engineering/mechanic training.
Other MB's have had widespread run away problems, just not advertised, that is one reason why pure mechanical injection diesels for automobiles are no longer made, and many new diesels have a flap to seal the intake.

The car is yours, as is the risk.
I wish you good fortune and hope it does not become a negative learning experience.