Headlight Bulb Socket Replacement DIY

Does anyone have a DIY for this, or could otherwise describe the steps in detail? I can barely get my hand in there, just enough to change a bulb, and I can't figure out how to remove the larger O piece surrounding the bulb clip...

I imagine there's some sort of fastener holding it in there that i just cant see. Is it even possible to do this without taking out the entire headlight?

Just twist and pull the black tab