1995 Mercedes-Benz S320 W140 M104 oil change using oil extraction only

1995 Mercedes-Benz S320 W140 chassis M104 engine oil change using oil extraction only. No oil left in sump after extraction. No need to remove drain plug.
Oil drain plug and oil filter cap torque is 18 ft/lbs or 25 nm
Takes 9 liters oil but I only use 8 liters which puts the oil level midway on the dipstick. Apparently that is what a Mercedes-Benz TSB suggests.