The glue isn't very strong, to remove them put a block of wood against the ends and hit it with a hammer (don't just hit the magnets as they will crack/chip) so they slide. I normally just re-glue them back in with better glue and put the clips back in, but i would try to refit your retaining kit if you can, maybe try and get ome smaller pins. The new motors have been made in Brazil for the last few years and dont seem as well made as the old German ones.