The part number for the "seals" on the fluid reservoir is 000-431-90-87(2 required) & list is $4.70@.
Where you have the LINE asking if you drain the reservoir here IS for connecting the hydraulic line for CLUTCH operation on a stick shift car. Don't cut or you will need a complete reservoir.
AT dealer WE always remove the reservoir & flush it with clean brake fluid & re-install with new mounting grommets, MB number 000-431-09-50 @ $3.40 (2 required)
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)