'73 Duster ABS headliner

I installed on about a year ago, I ordered it uncovered and installed it with the dome light, sun visors ...etc. I needed to trim back around the front and rear window then had it covered without my own material. It fits nice now but if you don't trim it the windshield gaskets doesn't lay flat.

Exactly!!!

I bought mine covered already, but figured out it needed to be trimmed back a little during install. I separated the covering from the front and rear edges, cut the ABS back a little and re-glued the edges and it fit great. The glue they used separated though, after some hot days (100*+) the material started to sag in the middle (not the part I did). I re-glued the whole thing with 3M upholstery glue and it's been fine since.

I think the moral of the story is to buy the ABS headliner bare, trim it to fit and then add your own material if you want it covered.