Steve
Is there such a detailed registry available for the BN6 Healey's, and how would you be able to tell if the VIN and body number plates are original or reproductions for the BN6's ?
BN6, I believe the BJ8 Registry is unique and there is no other one as detailed or actively managed. The long-time keeper of the BN6 Registry had his "database" on 3 x 5 paper cards until a few years ago when he turned it over to the AHCA and a new keeper was assigned. Each model registrar is free to document the details he chooses. There is no standardization among the various model registries and I do not know what kinds and how much detail the current registrar is willing to document. He happens to be the current President of AHCA, Gary Feldman.
The BJ8 Registry has been grown based on what information I have learned during 20 years as registrar that would be helpful to document in order to make the registry a valuable and useful resource for the Healey and BJ8 communities. I'm willing to put the effort into it to increase its utility and value and to make it a resource, but I don't think all registrars are. It's a lot of work, but I'm willing to do it because I enjoy it.
The more experience one has in looking at the plates, the more likely that reproductions can be distinguished from originals. There can be differences in the stamping font, stamping technique, placement on the plate, missing letters or digits, etc.