Sunroof Finish Panel Question

Many thanks. Thinking I am starting to understand how this comes together and have a few questions to clarify. On the panel with rectangular holes, this would have the plastic fasteners installed first and then covered with material, correct? Are there any connections at the rear or does the piece itself have a sort of guide like the ones at the front of the roof panel where the adjustment knobs are? Seems that adjustment could be made after installation by sliding the sunroof back a bit to pull down the filler panel at the front and slide it back for access to the knobs.

Can you clarify the area where the panel would slide in the photo below? I've put a blue and red arrow where I think you are referring to.

Assuming that chances of finding a good used or reproduction unit are slim, seems likely that this piece will need to be fabricated. When the headliner is installed does it overlap the perimeter of the sunroof a bit? Trying to gauge how close the fit needs to be so that it doesn't look bad.

Information is greatly appreciated.

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