The AZ plate looks very new (as does the paint) - could it have been issued/applied in 2019 (taking the first 2 numbers as the year - 1946 not so much). I see it is new to you. The CMC plate just links the COO to the body and isn't used for anything by DMV. Most builder don't mount the gold plate - I would pop rivet it on since holes are there. Most likely the COO (looks like a title but for just the fiberglass body) was turned in when the AZ title was issued - probably along with the VW title. The VW title linked to the Chassis # stamped into pan just forward of shift rod connector plate. Most states title using the VW Chassis# (many call it a VIN but it was before VINs - which were 17 digits). That VW # will give you the year of the donor pan which could be helpful for parts. Since you are in Oregon - you might try to register it as a VW fi you can. What year does the AZ title say it is? If it says 2019 - then some states will require emissions test for that year - with no ODB port (on any old VW) it most likely would fail.
Mike M has an early 1983 CMC - wonder what is CMC Invoice/body # is?
It seems strange that when selling a vehicle overseas - they want the build to have been completed 25-30 years ago. Doesn't seem to matter to them that its an old pan or kit was delivered years ago. It can be hard to prove build date unless you can provide a title/registration trail.