I decided to begin work on the Aston style fuel filler.
There are no holes drilled in the mounting flange but there are indentations to help. on the underside to aid the drilling of 6x m5 holes.
Additionally, fabrication of a rubber gasket is also required to fit between the body and the filler flange this was achieved using 1.5mm neoprene.
Care needs to be taken when actually installing the cap due to the curvature of the body so correct orientation is essential.