Sorry for being so thick but I don't know what you mean about a clip connection... is what I have circled in red the connection you're talking about? I've been prying at that with no luck. Orange dashes are where I wanted to cut, if the connection just pulls apart it seems it would be easier to cut it off and then pull the fitting out maybe with pliers. The way it sits right now I barely have room to pull the connection apart, not being attached to the inlet would help a lot.
Green circle is the the BPV return and that one should just slide off right?