The bonnet has been modified in a few different areas. Both for cosmetic and functional reasons.
The most obvious being the scoop and vents. The scoop and vents are functional. They assist with the cooling. The scoop actually forces air onto the engine when in motion and the vents let hot air out from the under bonnet area when stationary or moving. I also think they look good.
The scoop is from an old Toyota Supra and the vents are from a local boatyard. I gather they are generic vents used for many marine applications. A big benefit of them being Marine equipment is that they are made from marine grade Stainless.
In addition to the scoop and vents, the following additional mods have been made:
To allow for the Servo on the brakes, a section of the rear of the bonnet had to be removed. This was easily cut out using a jigsaw. Its not very clear here but if you look carefully you can just about make out the cut-out on the left of the picture as you look at it. You can also see from this picture the holes cut out to provide the cooling from the scoop.
The Original Bonnet catch was removed, as the modified front grille section and relocated/modified Radiator mean that it would no longer fit. The bonnet is now held down by Stainless steel catches.