Difficulties Installing ABS Headliner in 73 Swinger

What did you think of # 5 for holding it up there and being able to get a breath? Being a one-man band with a homemade specimen I had quite an operation going. I did use like a four foot level with some other stacking pieces to hold it up in other places while I worked on things. But I concur that digging it into the back was the easiest way to do it but when I did it my windshield was out so I just let the windshield installer get around the front for the most part but I had to trim it back and make sure that that gasket would fit when that day came and it did. Oddly enough my copy that I made the pieces I had left of the original was a little long in the front like everyone seems to be complaining about what these abs is and where they're ending up trimming them. It must just be the way we can't get it to origami like the original?
#5 is a key step. Very tough to hold it up there without pinning it there.