Nope - it should sit around the outside of top ring, so you can see it when fitted.
They are bloody tight when new, and really awkward to fit. Having at least three hands is the way to go! They seem to just pop off by themselves as they're under pressure.
I found myself using a mallet wedged between the filler ring and my chest to apply pressure onto the filler ring, leaving both hands free to guide it all in place and tighten the grub screws.
You're also missing the big O-ring which sits in the groove below the grub screws in your pic ... unless you've just not fitted it
