Valve removal quick question

[Praxiss454]

I pulled the head from my L6 230 for a rebuild. I'm trying to pop the valves out but the first one doesn't want to come out. Here's what I've done.

1. Use spring compressor to compress spring down. I had to tap the top of the valve with a rubber hammer to knock the cap free.

2. With spring compressed, remove the two halves of the V shaped retainer clip

3. Pulled the spring off.

Now I'm looking at the valve, just sitting there in place. I can move it up and down freely, but it looks like there is another solid ring stopper that is holding it and preventing me from pulling it out of the bottom of the head.

How do I remove this ring? I'm afraid of screwing something up so I don't want to force it. It seems to be solid all the way around, and it seems to be sitting in an indented channel on the valve, similar to how the retainer clip sits.



Any tips are much appreciated.