As others have done, You might also consider making the top cover of the tunnel more than one piece. We cut ours four screws back from the firewall, then at the fuel selector, (it slides under the third panel at the join) then just behind the front seats, so finished up with four panels. The first just behind the firewall basically stays put, the panel top to access the fuel system is a lot easier to remove if you don’t have to get those eight front screws out. The third panel is under our home grown console, so just behind the front seats, the fourth gives access to the flap motor. Used the original cover and riveted extensions under one of each at the joins with Nutplates (we used four on the top) also one extra Nutplate on each side at every join. (if the cuts are made just past the side screws then easy enough to add one extra so each panel has the same security. Cheers from Western Australia