Are there supposed to be plastic clips with each bow? The only ones I have clips for are the very front and back, and the middle one that goes by the dome light? It looks like that's all that is really needed.

There is a plastic clip for each one. If you don't put a clip on the center of all 5, the listing bows will move around as you are tensioning the headliner.

69 sleeper, are you sure on that. I did my 67 and I don't remember the plastic clips. I anchored the center bow with metal tabs if I remember correctly. Then just stretched front and rear, & side to side.

All the headliners I have installed have had clips for each bow (whether they were metal or plastic). My '69 used white plastic ones that fit into a slot in the roof bows. I remember on the first headliner I did I did not have clips on each bow and when I went to tension the headliner I couldn't control the wrinkling.