Sail Panel Installation... What Type of Adhesive?

I'm about to replace the headliner in my son's '68 Dart and would like opinions on what type of adhesive to use to secure the sail panels to the body. The sail panels I have are new and will need to be formed to fit the curvature of the rear panel. What adhesive will hold them securely so they don't pop off.? Or should I use a flathead screw to hold them in place while the glue dries (since the screw head will be covered by headliner anyway....).

Thanks,

Mark.