Of a 7750 Valjoux? Verzonden vanaf mijn iPhone met Tapatalk It's very easy. Unscrew the crown. Then press the button close to the stem, not too deep, just like half a millimeter. You can pull the crown and stem out. Verzonden vanaf mijn iPhone met Tapatalk To place back just bring the movement in position, don't attach the holding clips to the movement yet. Carefully push the crown in the hole and turn it a bit until you can push it easily further to the point that it's against the bar connected to the button for removing the stem. Push that button and the stem deeper and let the button click back. Now the stem is locked again. Verzonden vanaf mijn iPhone met Tapatalk