You have to:
1. Reattach the head assembly to the mic frame by re-inserting and tightening the three tiny screws you took off, as shown in your picture
2. Carefully insert a sharp knife blade into the crack visible between the nickel-plated ring that covers the actual head basket attachment screws currently hidden under the ring and the head basket (yes these are two separate parts!).
Work the knife all around so that the gap between ring and basket will become bigger and bigger, until you have dislodged the cover ring. Do not force the knife, but let it gradually lower the ring.
Once the ring is off, you will see three tiny slot screws which hold the basket to the basket frame. Remove them and you will be able to lift off the basket, giving you access to the capsule assembly.