Just have them do it, because it can be messy. Be sure to print out the procedure, because it really doesn't exist in any of the MB books. I would pay to have about 1.5 qts. new fluid flushed through, and leaving you enough for fill.

Also, as Preventative Maint. (PM) replace the hose between the resevoir and the pump (don't ask me how I know).

:-) neil