PartsShop vs. manual: No steering filter?

Busy rehabilitating an '83 380SL here. The
fluid in the P/S reservoir was pure coal
black when I checked it. Thought I would at
a minimum suck out the old fluid and examine
the screen, perform a temporary ATF refill,
then order a new screen from the PartsShop
for a full drain job later on.

Drained reservoir using a suction tool from
the top, expecting based on other posts here
to find a filter at the bottom of it. Nada!
No filter! Only a ring of round holes that
might possibly filter a pachinko ball. And
I can't see where a filter would go, either.

There is a shaft coming up from the center
of the ring of round holes, with a spring
concentric to it. The reservoir cover mounts
to this shaft. But that's it.

Looked in the 107 svc manual and there is no
reference to a filter in the P/S system. But
the PartsShop has one listed for the 380SL
for that year. Am I confused? Is there no
filter from the factory, or did some inept
wrench just leave it off this car at some
point in the past? I assume that the guys
running the PartsShop are up on their game.

Anyway, I refilled with clean ATF, drove,
steered lock to lock a few times, found the
fluid filthy again. I'm going to drain and
refill a couple of times (Dexron III) as a
stopgap until this question is sorted out.

Thanks in advance to anyone who can solve
the mystery...

Ron H

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