Hi,I've just attempted a temporary fix to my sagging headlining and thought I would let you know how I done it,first I unclipped the rubber seal around the tailgate and then gently pulled the edge of the headlining down to expose the massive void between the fibreglass and the material,I the sprayed liberally both surfaces with a contact adhesive,waited for a few minutes then starting from the back of the sunroof I used a warmed up travel iron to press the cloth back,working from the centre to one side at a time,it's not perfect but does seem well glued,we will have to see,only took me ten minutes and made realise how dirty the headlining is!