For what it’s worth, the plugged port in the front of the water pump is what the later motors used when they had an oil cooler. Can’t say exactly when they changed it, but probably after 2014. :)
Yes, my 2019 uses the tapped casting ports. But thermostat housing is a viable option for a heater hose on a 6.1 or any pre eagle and not worry about the water pump interchangeability