In the process of bringing a 1970 m818 back to life...Just finished new head gaskets / top end overhaul and some new injectors...all went well and she came back to life with surprisingly little effort... I just finished flushing the coolant system using dawn dishwasher soap and many rinses to get the system clean... Does anyone have any tips or tricks on replacing the thermostat on the 250 Cummins...any help would be greatly appreciated... Thanks