'32 Roadster - Flushing Motor & Radiator

[1962300]

I foolishly let my '32 sit for over a year & now it heats up to HOT way too fast.
I want to flush its '32 Radiator and 59A Block.

Is the simplest way to remove a lower hose from each side & run water through the radiator, until clear?
I probably need to pull my upper hoses & confirm my thermostats are not gummed up & working.

Anyone like this product:
https://www.norosion.com/norosionflush.htm
(Along with their rust inhibitor)

Thanks!