Here's my plan, draining the radiator gets out approx 7 quarts. Refill with 7 qts distilled water, drive with heater on, drain, repeat twice. Then measure in 5 qts of concentrate and top off with distilled water. The cost of distilled water is cheap and our local water is high in mineral content so I'd rather not use it. After a triple rinse I think the system would be pretty clean of the old coolant. This makes the job simple and clean.
What do you all think?

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Brian
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