Technical Shoebox Headliner Bows

Hi All,
The headliner bows in a 50 Ford, are they just spring held in place or are they attached along the roof with some sort of bolt/fixture setup? They seem as though they would rock back and forth without some sort of attachment.
Thanks, Steve

 

The listings on the headliner keeps the bows in place and still allows them to float as the headliner is tightened fore and aft.

 

You're telling on yourself. Each seam has a housing for each bow sewn in with it.