That does provide some visibility into how it goes together, although it's not clear to me how the Y hose mates to the three parts, or how it would be de-mated from them. It also has me contemplating ****-canning the entire assembly, as I'm not impressed with what I'm seeing, from an engineering standpoint. The push-pop drain on this thing is also jamming up, which contributes to my growing inclination to punt on it and replace with a conventional Moen or similar that's readily serviceable, unlike what appears to be the case with this trying-too-hard-to-be-cute POS.
Thanks for the follow-up help. Muchly appreciated!