its been a long time since I did a 66-67 nova, but I seem to remember a small curved metal piece held in place by a small trim screw. hope this helps.

I'm pretty sure that car does not have the small trim part. If there is no screw hole between the top of the a pillar and windshield, then there is no trim that goes between. In that case just fold the raw edge under leaving a nice edge between the top of the pillar and windshield. If your liner has the pin holes just use a small piece of seam tape/double sided tape instead of gluing the material to itself.

I looked at pictures of a 66 i did a while ago there doesn't seem to be a screw hole.

Thanks for the help. I was wondering if there was one or not. Nova weren’t the fanciest models of that time so I could see them folding it over. I realize the rear tack strips are missing. Anyone have a good link to were they can be purchased.

One thing I thought about was using convertible top rubber tack strip. Using that, gluing it into place and then coming back with some #6 screws to further hold it. Counter sinking the heads and stapling to that.

https://www.classicindustries.com/product/1966/chevrolet/chevyiinova/parts/k6010.html

sorry I was thinking about the trim with that last link i posted. I don't think that car has a traditional tack strip. It should be glue on all the way around. There should be some metal strips with the small triangular tabs/hooks if i remember correctly. Then once the liner is installed you would use the part (in the link from the previous post) on top just like a pinch weld molding/ snap on trim/ snap on windlace.

The trim piece for the windshield has a piece on the end that covers the A pillar. So you fold the headliner and the trim piece covers it or you can glue it and trim the vinyl

Thanks for the help everyone, got it all buttoned up Sunday. Like Robert said it’s a little plastic piece that goes over and then the headliner is folded up. The rear window trim that Andy showed was a pain to get to fit the car. It’s plastic pieces that all intertwined around the rear window to help hold the headliner. I could see before I started that each pieces profile didn’t match the profile of the piece that it slipped into. Had to get creative but made it work.