I try to pry out the stuck thermostat with the screw driver and did not work. So, i tried to but the rubber gasket part of the stuck thermostat with the knife. The result was tip of Boker Kashinikov knife broken off. Time to shop cheap carry auto.
Or spend a little more for a not-cheap auto and not have to replace them every time they break. Not saying a knife made out of better steal would have survived but it would have. ;-)