Question about coolant amount

I have a 94 C220 and am wondering how much coolant it takes if I want to do a flush. Is it 8 L total (50/50 with distilled)? And is this amount in reference to filling half way up the expansion tank? I'd like to know the exact amount because I am going to back calculate the ratio of coolant to mix (a little over 50%) based on the engine block being filled with 100% distilled after I flush.