I've always reversed flushed my stuff. Get a tee fitting and take the top heater hose loose from the motor. Get another piece of hose and connect it to where you took off the hose and put the tee between the two.
Connect your garden hose to the tee and take off the radiator cap.
If there is a valve in the heater hose to shut off water to the heater core open it.
With a thermostat in place it will stay closed using cold water and the water will be forced down thru the motor and up the lower rad hose and thru the radiator and out the top, back flushing the system
When the water runs clean your done, pull off the tee and small hose and reconnect the top heater hose.
Don't forget the anti freeze.
Dan

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