I remember how to do that with the 4022 cardioid. You have to screw the capsule (the whole little thing, not only the grid, of course) from the impedance converter, then you have access to a snap ring (circlip) which you have to remove. After that, loosen the cable clamp on the back side (counterclockwise) Then you can pull the ceramic pcb out of the housing. This ceramic element is very delicate and you should only do anything to it if you have good soldering skills, otherwise you could easily destroy it. I cannot encourage you with good conscience to try it yourself, but if you are familiar with things like that, this should be the way to go - at your own risk !!
