I haven't quite figured out how the squeeze safety works. I have both models from 1973 presumably new in the box. The removable pin is under the grips as it should be. There are actually 3 holes these pins can fit in, storage hole, upper safety hole and lower safety hole, for lack of better description. With the pin in what I'm calling the storage hole the guns will both shoot all the time. With the pin in the bottom safety hole the guns will shoot all the time. I can't tell but very little difference in the position of the safety. Is it the upper pin that has to be removed for the safety to function? Therefore, a pin stays in the bottom hole permanently? Help please!