How to replace headliner with a precovered ABS piece

[BBcallaway]

First picture... Hook trim piece from outside first then just kinda of roll it until it snaps on the inside.

 

[standupjskiguy]

Off the top of my head, the first picture looks right because it closely matches the trim piece that fits over it.
I.E. the trim won't fit if you have it like in the second picture.
Let me caution you about that stuff you have on the ceiling.
I tried that on my 68 Camaro. When it gets hot as if sitting in the sun, the stuff I had fell down onto the headliner.
Park your car in the sun and see if it comes loose before installing the headliner.

 

[BBcallaway]

I have had no issues with my headliner this summer..
Thanks for the tip though.

 

[Dave Dunbar]

I had mine done, plus the visers. Cost me $120 CND. at the local body shop.