As drive shaft was remove keep an eye out for any oil seeping from where the shaft enters the gearbox. I can't recall on the Croma box if the natural oil level is above or below the shaft level/seal.

It is the whole bulb unit that comes out. Can't remember which side you gently prise up first. On one side it locks in via a rib beneath the bump. On the other there is just a plastic curved spring lever. One side will be lift able and the other not.