It's important to remove the filter and use lint free towels (think blue windshield towels) to wipe up the black sludgy crud in the bottom of the reservoir .

The best way is as mentioned, to remove the drain plug in the steering box but the average DIY'er can simply use a Dollar Store turkey baster to suck it all out then clean the crud , re assemble and re fill, then repeat every routine 3,000 mile oil change until the fluid remains red and smells sweet .

This works fine and is the lazy way to go, many DIY'ers don't like to jack up the car and so on so the important job never gets done .

Whilst you're doing this, check the back of the drive pulley, is it's wet the input seal needs replacing, another simple job that requires no special tools, just time, some effort and clean LINT FREE rags / towels .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better