That model looks like it uses a similar system to the 4623 calibre quartz's for retaining the crystal. When the bezel is removed the crystal and chapter ring come out with it, the crystal then has to be pressed out of the bezel which presses out the chapter ring with it. A further complication is there are two gaskets, the rubber one sealing the crystal and a nylon one holding the bezel on. I've just replaced a couple of crystals on a pair of 4623's, and dismantled and had to reinstall the original crystal on a further one as I couldn't source a one with the exact dimensions and bevel for that particular model. Not the most straight forward cases to work on! I have another one to do which will be on the bench in a couple of days which I'm not really looking forward too.

Anyone attempting to replace the crystal on one of these types that have the chapter ring pressed into the bezel will need a decent bezel remover and press to get the job done.