Steve,
I pretty much have the V4F addendum memorized, but as it says on the first page, "If you should have certain modifications to V4/V4F engine blocks in mind and they are not listed in this Guide, they are probably PROHIBITED!". I have also found, from personal experience, that even though it's in print, it is still sometimes open to individual interpretation.
To further streamline my question, I want to ensure that a modern DOHC head can be used in a Vintage Roadster. For instance, in blown V4F, a turbo may be used in Special Construction, but a vintage roadster must use a supercharger. Just hoping for 100% clarity that this isn't the case with an aftermarket head.
Thanks, Pete