I have read many threads referring to 203 and 195 degree thermostats. Ford's OEM was the 195 while International used a 203 in their setup of the 7.3. When thermostats are manufactured, there has to be a tolerance + or - some degree or partial degree. I couldn't find out what this tolerance was, but this probably varies by manufacturer. At face value, we are talking about 8 degrees. Does this really make that much of a difference? I would understand higher differences making some changes. If you have some input on this, please respond so we can get to the answer (hopefully) of 1-what does the 203 give you, good or bad and 2-what degree thermostat is the best for the Powerstroke?