Something that was not discussed in that article was the cooling system.
I run race gas.
Personally, I add anti freeze till it's sufficient for our climate, add Stabil to the fuel, run the engine for 15 minutes to circulate the anit freeze and Stabil the fuel system. THEN I drain the fuel and cooling systems.
If for sure I'm doing a teardown, then it all gets emptied, drained and stored before freezing temps arrive.
If all you do is drain the cooling system and you have an aluminum radiator, then DO NOT forget to pull the radiator and drain out that last bit of water in the bottom ! Unless you have a drain plug/valve in the bottom you will end up with two split tanks in the lower sections !