Looking at the pics of Murdos car, it seems to me that the Ziebart was skimped on a bit!
Hi Steve, the areas covered by Ziebart was a customer choice, the same as any corrosion protection today.
I've spoken to the original owner (Geoff), what he had done was his request rather that the Ziebart agent's - the engine bay had only the strut tops done and the boot area had in between all double skin panels done, every other part of the car was done as normal - he didn't want to have the engine bay and boot area covered in Ziebart purely for visual reasons, and both are original and immaculate to this day. So it wasn't skimped on but done how the buyer wanted.
He also had and additional aerial fitted, to the rear wing, an electric one.