Does anyone know what needs to be done to remove the movement from this front loading IWC case? I removed the crown (and split stem) and pushed the other half split stem back into the first position (as one would do when removing a unishell SMD). The movement seems to be held in place as it doesn’t budge at all but I can’t see any sort of clamp or tension ring that can be adjusted. Any thoughts? I’m wanting to confirm that the case is solid 18k gold as advertised but can’t make out the hallmarks on the case.