I'm surprised there are no engine pictures. Classic Roadsters is a Canadian firm from what little I've researched. Not much on them:
Classic Roadsters - Home
Typically, those of us that have bought either an SPF, or built our own, tend to have a fairly straightforward process for registration.
If this does in fact come with a 427 installed and can verify the serial number on the engine block as being a 1966' 427 side oiler, the issue then becomes the transfer of a vehicle (assuming it's out of state) and then it's an issue of whether it was originally registered in it's current location, before being sold to you here in CA.
btw, if you're inviting, you may want others to come because I'm not an expert in a 427SO. I'm a small block guy.
You'd might want to consider either Steve or Ted plus a couple of our guys to give it a look over. I say this only because I have a Factory Five perspective, whereas most other have Superformance knowledge. Kit cars being what they are, you want a variety of eyes because no two people build cars alike. Steve and Ted see all sorts of vehicles as well as SPF's and other kits so their input would be more valuable.