71 Duster: how do you remove metal and vinyl trim under pop-out windows?

I'm quickly beginning to understand why the labor charge is so high to install a new headliner. It is tucked under the trim on the sides and under the front and rear window gaskets.

I'm pulling off the trim inside my car and I'm currently stumped while trying to get the metal piece off that is partially around and under the rear pop-out window. With screws removed and the back part of the metal pulled away from the side a bit - I can see that the metal trim needs to slide forward - towards the front of the car - but it seems to be held by something under the vinyl trim that is below. The vinyl trim is another thing I want to remove - but can't tell how hard to pull where without breaking something. Are there screws under the vinyl that are holding the metal trim above?

Some tips here would be appreciated - I don't want to destroy this stuff while trying to remove it.

tx,
Ken