I learned the hard way with my Century Arabian that a major concern in winterizing is the coolers. I warm up the motor, drain the block & exhaust manifolds, start the motor up, run 100% antifreeze through it and then drain everything I could. As cold as the winters get here in Michigan, I have never had a problem except the first year after I had to replace an oil cooler on a 25 year old boat. I fog the motor as a last step.
Did I mention I hate winter!