I feel foolish for asking this question, but I figured I better suck it up and ask here before I mess up a movement. Awhile back I purchased four ETA 2824-2 clones to use for practice assembling some custom watches. The problem I keep experiencing has to do not with removing the stem, but in getting it properly re-inserted. I remove the stem while it is in the time set position by using a small screwdriver just slightly smaller than the stem removal slot. The stem pops right out, no problems. But after sizing and cutting the stem, I find it nearly impossible to to lock back in to the place in the movement. I'm very gentle when removing the stem, so I doubt I'm screwing up the keyless works when removing it. The stem removal button isn't stuck down or anything. I've tried re-inserting the stem both with the stem removal button pressed and other times while not. No matter what I try, it seems to be hit or miss whether I'm going to get the stem locked back in to place. I've managed to do it successfully with just one of the movements. Two sit on my workbench for months now, with me unable to get the stems re-inserted. I have one more untouched movement remaining and I'd rather not screw this one up. I'd appreciate some insight in to whether I've somehow ruined the keyless works on these movements, or whether I'm making a beginner's mistake and missing an important step?