Just bought a Rowan Crown 24, it has floppy headings but they are still in position. I am considering fixing battens to retain them, and I thought short screws through them into the deck head to hold them while bonding of the battens goes off, I would just make a small cut through the lining, a good lump of mastic and then screw the batten up gluing the headlining and batten up.
The only way to do this properly is to take the old headlining down and disregard. Bond some strips of wood on to the bare fibreglass (1” x 3/4@). Make some quarter ply panels to fit – I suggest having about three pieces. Glue new leather cloth on to the panels using PVA glue rather than Evostick. Pull the edges over to the back and staple. When all dry, screw covered panels to the strips of wood. You can either use hardwood joint covers (using one screwed strip over the edges) or screws and cap cup. Only use stainless steel fittings.