I have a couple more questions about starting my engine. I'm hoping to try and fire it up Sunday. As far as cooling is concerned, is it better to have or not have a thermostat installed during break-in or doesn't it matter? Also, should I fill the radiator with coolant or run pure water or again, does it matter one way or the other? I was thinking of running straight water in case something goes wrong so I don't lose the new coolant that I bought. I'm going to do as suggested and not install the clutch fan and just use one of our box fans to blow through the radiator.