[Chrysler300] headliner retention; molding etc 1957 coupe

Is anyone familiar with this setup, and it’s variations?

Car is a 57 Dodge but superficially the headliner setup looks same as a like year 300, it has perf cardboard placed between metal backing strips that are behind the headliner ; these metal “span” pieces are probably use in all mopar ; the 300’s have stretched fabric, probably over same metal framing pieces ? For those who have never gotten into this, (includes me, till now ) all this can be taken out after removing rubber window seals and related trim parts , little covers on each outer trim end slide up , exposing sheet metal screws; that releases the back spanning support piece from the car body. .It is about 1” wide with a raised center rib about ¼” wide that the finish trim snaps over.

The problem is the beige color plastic outer finish piece seems to be designed to snap onto the metal. Made of Plastic on this car ---but aluminum looking on others? The plastic has hardened and breaks readily . I have looked at a few other restored 57, again Dodge ---but some 300 might be same, and the restorer (in desperation?) had cut the trim in half trying to get it back in (looks awful) ; it came out of the car ok in one piece with the metal and old headliner , and even got it off the metal without breaking it, but trying to assemble all this in place in car it fractured .Does anyone make those outer trims? Kind of a lesson in this , is tread lightly on tearing into replacing headliner**…had to do it in this car it was falling down.

Normally the plastic cover trim apparently holds the panels in place (nice to thing to assemble…!! 4 hands) ; we are looking at skip gluing the headliner panels to metal strip , so trim then becomes just an aesthetic closure

General comments welcome on this issue… I doubt the original plastic can ever be gotten on again, already some damage trying… **so left with a big now what…..