3 quick questions on Radiator Flush... 2001.0 QX4

[Legend11]

My truck has 127,000 miles on it and it has been time for me to replace the entire coolant in the cooling system. I plan on changing/flushing out my coolant when spring arrives (I will be running 100% water for a couple days and can't risk any frozen lines). I've done a ton of research on flushing the coolant for my truck, but I'm a little stumped with a couple of things...

1) Before I put in the new coolant. I plan on flushing multiple gallons of distilled water through my cooling system to completely eliminate all old coolant, contamination, etc... I want my drains to be completely clear before I even consider putting in the new coolant. Is there any harm in temporarily driving my car with 100% distilled water during these days (maybe a week's time). I will be continuously flushing out the system until it is completely clear and want the heat from driving to help dislodge any junk that might be there. Just want to make sure there won't be any harm in doing this with good weather. Also, should I mix any flush chemicals at this time or just 100% distilled water?

2) After the distilled flushing phase (100% clear drains), I plan on purchasing 3 Gallons (12 quarts) of Blue Genuine Nissan Fluid. Unfortunately, this coolant only comes in 50/50 and not 100% concentrate. The QX4 cooling system's capacity is 9.75quarts (including reservoir) so this should be enough for the job. I am aware that a Radiator Drain will only drain the radiator and not the heater core or the engine block. I want to avoid removing the engine drain plugs (will only be using the radiator drain plug to remove coolant) since they sounds like a PIA to remove. Are there any other effective ways of removing this distilled water from the block and heater core to help me get a 50/50 mix? I considered removing the the upper radiator hose and extending it into a bucket. Pouring 50/50 antifreeze in the radiator and continuously pouring it into the radiator with the car running until blue starts spitting out of the upper radiator hose and calling it good. Is this the best approach?

2) In addition to the coolant, is there anything else I should replace at this time? I will be inspecting the 2 radiator hoses. Should I replace the thermostat? Anything else?

Thank you for any help!

[Kompresshun]

I would not recommend running straight water during this time of year, because you risk the engine block cracking if the vehicle sits in freezing cold temps for too long. If it were summer, there wouldn't be quite as much concern but plan a day and just make it into an all day thing. Two flushes should get everything out with no problem and then I would definitely change the thermostat while you're doing it for good measure.

If you have no record of when the belts and hoses were replaced either, it wouldn't be a bad idea to do those while everything is apart.

Your method sounds fine, but I wouldn't overly stress about it. Just flush until the water runs clear, then let it all drain out. Fill it with the proper mix and it will be fine. If there's any left in the system it will be so little that it won't matter.