I've been putting this job off, but came back from '300 sailing early today as I just couldn't keep up with the others in the strong breeze - great sail though.
I cut some ply 'washers' to use to clamp the panel along the girder and dug out the wallpaper steamer to soften the panel
Turned out to be really straightforward. I'm pleased I took the trouble to steam it as this is quite a curvature. Next stage will be to mark the panel, remove it and trim it some more before co-opting some helpers to glue it down.