i recently inherited my family's 82 Westfalia (only 101,000 miles/no rust!)
and i only had to badger my grandfather about it for nine years.  the reason
i write you folks is that when it came time for another state inspection,
much to my surprise, it failed.  reason: no catalytic converter whatsoever.
i asked my grandfather about this, and he said it never had one.
explanation: my stepfather had bought it new in West Germany then driven it
around Europe for a month or two, shipping it back to the states later that
year.  He told me that in 1982 Europe didn't require catalytic converters by
law, and that nothing had mentioned upon its arrival in the states (and
since fuel economy was improved, he saw no reason to say anything).  getting
it to pass had always been a matter of going to a local garage that "failed
to notice" it was missing.
i went to the VW dealership and told them my predicament , and a parts man
told me that since it was shipped here without one, it was exempt from the
catalytic converter requirement, but that i should check with the state
police office in Richmond to be sure.  turns out he was right.  the state
police confirmed it, twice.  once with me, and again with the service
station mechanic who didn't believe me.  it was also interesting that they
didn't require any proof (import receipts, serial numbers, etc.).  i
could've been lying my pants off, and it wouldn't have mattered one bit.
i don't know if this exemption exists in any other states, or if indeed
applies to any of you out there, but i thought it was interesting
nonetheless.
have fun,
jason