I take it all back, the scuttle panel is as much 'fun' as the rear panel :)
I did only spend about 20-30 minutes on it this evening. The panel is not quite long enough to reach around each side without the help of a ratchet strap (padded) & while the ends are in place along the side panels its slightly deforming the firewall panel so will need some fettling:
I have the clecos in the front edge, It will need dismantling and the tabs adjusting before anything is fixed permanently:
It can sit like that for a couple of days, then I think I'll drill out a line of rivets along the rear edge to fit the inside panel. I also want to offer up the bonnet before bonding and fixing the geometry of everything:
Need some more M6 20mm washers!