Found this number down near the spare wheel well:



It matches the serial number pattern of a '74 standard - but as mine is a super, it can't be that a panel from another car has been used at some point; is it a part number?

its the production model number for the aussie factory.
Its the code for Superbug with 1600 engine

If you still have the logbook for it those will be the numbers in the model #

Oh cool, so does that mean that mine is the 7,421st of its type built by VWA?

Sadly I don't have any books for the car.