Driving my 67 the other day (Tucson) with the window down and the headliner thread gave up.
Looking like it is savable but I have my doubts.
Don’t feel like taking the glass out, twice anyway.
(Still have to paint the car)
Razor blade time? Not drivable as is.
#2 thought going thru my head, 3” exhaust (single) workable?
Thanks 
The only way to fix the headliner is to glue it. That means buying a new headliner and removing the front window, rear window and buying new rubber seals for each. Additionally you need to replace the perimeter seals and the seals under the stainless steel strips securing each side weatherstrip. It’s a big job.
Royce is correct. Ive seen it done without doing those steps and its always half assed. Do it right the first time and you will thank yourself later. However you mentioned painting the car and if that is going to happen sometime soon I would wait to do the headliner until its painted.
You may be able to patch it somehow to keep it driving until your ready to install a replacement
Thanks for the replies!
Getting my wife to look at it tonight.
She said it is her car!
Just an FYI, no matter how you decide to proceed with the headliner be sure that you keep the headliner bows in the exact same order as you remove them. Each bow is unique and must go back in the same place as it came from. The bows are not interchangable. Also the very last bow (the one closest to the rear window) has a pair of clips that hold it in place and keep it from rolling over.
Randy Goodling
CCOA #95
Just did the headliner in my Corvair. Same with the bows. Happy for the reminder!
Might see how magnets hold up until it’s ready for a new headliner. Just waiting for my Vintage air due on Thursday!
As my dad always said, “good enough is not right, but right is good enough.” No shortcuts on a headliner. You will have issues otherwise.