DanielW-
Nobody has responded, so I'll take a shot in the hopes that it may help you...
I have the parts diagrams/numbers for the W140 Coupe, but not the sedan....
Dug out the documentation today... wow, there are a lot of parts in the door trim assembly. I can't be positive, but think I've identified the pieces your talking about.
Yes, it appears that every piece and screw has its own part number.
IF the trim cover is the same for the Coupe and sedan (I suspect it is), the numbers off the fiche are:

Left Door 140 727 17 88
Right Door 140 727 18 88

Hope this helps.

__________________
KenP

1996 S500 W140 Coupe