Bingo.
I would do the break in with just water, then add a little antifreeze or water wetter afterwards mainly for the lubricating properties (keeps the water pump happy).
Also, have a fire extinguisher handy when you do the break in.....I only had a garden hose handy back in 2001 when I was breaking in a 360 I built. The remote oil filter line ruptured 13 minutes into the cam break in and shot hot oil onto the headers making a HUGE fire ball. My friend just reacted and pulled the hose out of the radiator and sprayed the oil fire with water (not realizing it was an oil fire) making it worse. I simultaneously ran dove head first into the car to kill the motor. Once the motor was off the fire died quickly...I got lucky...no real damage other than some scorched wiring....and we had a cool little fire floating down the street too, lol.
The moral to this story, ALWAYS HAVE A FIRE EXTINGUISHER.