Find location for VIN, Vehicle Identification Number (Primary one)

Hi,
I bought a Chevrolet Corvette C4, 1984 in April 2015. When i now in May
drove for the car inspection (in Sweden for this 32 year old Corvette the car
inspection are every two year). Everything was ok from a functional aspect.
BUT they adjusted the rules regarding primary and secondary VIN (Vehicle
Identification Number) and then the problem started. I have the secondary
one below/behind the windshiled + i have the original label om the driver
door. But we could not find the one on the chassis or beam around the
engine and the whole way back on the underside i also used small mirrors
as some had ideas to look on top of beams... I tried to search for this via
different ways - communities in US and Sweden, asked people etc. but no
specified answer. No one asked/looked for this earlier when the inspection
was done. On Mnday June 20 my car get driving ban. This is not fun at all -
i mean the car been on our roads in 28 years (was imported 1988). This is
to avoid that people mix cars and build from different parts. But this one
never been stolen, crasched or rebuilt and the identiy never change during
these years.
Does some have any ideas where to find the primary one?
Regards Jan