demon 1 pc. headliner question

Hi- as mentioned before, took my Demon apart several years ago, and I am putting everything back together (slowly)- will be putting the 1 pc. headliner back in soon and need some help. I dont remember exactly what it is that holds it in place and was hoping someone could give me an idea as to what I am looking for (pics if possible)- had to move the car recently out of the storage garage I was in and may have lost/misplaced these items, but I really don't know what I am looking for. Thanks for any help