One job that has been outstanding for a long time is the actual drill and fit of the Aston fuel filler cap. M5 holes were drilled and then countersunk within the flange on the filler. A grommet was made from cutting 1mm rubber which was then mounted between the flange and the car body.
Be wary – when screwing the actual filler, the curves of the body mean that there is an optimum position which enables the release flap to operate the filler. An IVA requirement is that the locking fuel cap is tethered to the vehicle, this was addressed by drilling a small hole in the filler neck and anchored to this and the base of the locking cap with picture wire.