Thanks.

The sleeve is broken clean such that the upper part is flush with the inside of the group head, looking like it belongs there in the first place.

As there is nothing sticking out for me to hang on to, I may need to somehow stick in some sort of "jack" to jam against the hole to twist the whole set out. This will be a challenge for a non handy person like me.

Waiting for the healthy part to arrive to further study.

Still waiting for the broken sleeve liner to arrive. While waiting the whole set popped out again. So I thought I would take a picture of the sorry state of the plastic liner:

The bottom part broken clean

http://sphotos-h.ak.fbcdn.net/hphotos-a ... 127152263a

Top part stuck inside the group head

http://sphotos-h.ak.fbcdn.net/hphotos-a ... 2e34bf20dc

It will be quite a job to take the top part out.