took radiator off to go to the radiator shop. haha could not fix.. after puttin in car wet backto look at tractor. and at the top of the thermostat housing was a retaining ring about to fall out cause the thermstat had pushed to the top, i tryed to pull it out to look at this stat like ive never seen before ,,would not come out , so i pushed it down and it went back in enough to put retaining ring into grove ,to hold in thermostat ,, ,but before i put it in i tryed to get stat out ..grabbed center that pops up and its spring loaded you can feel it ,,the stat comes up to top of hole no retainer and stops ,,so i stopped ,an pushed it back down and put retainer back in....well my question is how do u get it out and whats under there and wow i have never seen a stat that well made man we built stuff right in the old days i wish things were that way now,but how do u get it out..i wanted to test it if possible....thanks dewy