Welcome Brian,
Was that you with your family, at the Mecum Auction in Indy? We spoke about your car, as well as the Vette Fest.
It sure seems to be a very cool car you have.
Your Father had mentioned that he was going to send us copies of the supporting docs he had, to show that the car had been sold new out of Nickey Chevrolet.
I don't know that we will ever be able to Certify your Car as a "Nickey" Conversion, as the car was built by GM.
There are generally 5 broad classes of Muscle Cars/Race cars sold out of Nickey Chevrolet or Nickey Chicago.
1) First are RPO Muscle cars and Corvettes.
Example; We have Three ZO6 Corvette, Big Tank, Big Brake cars in the Registry; One is the 'Nickey Nouse' Race Car, another is the built for AJ Foyt Race car and the final one is a customer sold car.
This last car is classified as a Nickey Sold Car and is included in the registry as such. This is where I believe your car may be included.
2) Next we have Nickey Super Tuned Cars. These are cars which generally kept their stock engines, but had other Nickey Hi-Performance Modifications performed when New.
3) Then there are cars, which were transformed/Converted into "Super Cars" when New. These Conversions are the cars which became "Nickeys".
4) Also there are a host of Nickey owned and built dedicated race cars and we classify them as "Nickey Race cars".
5) Finally, we have Nickey Shop Conversions, which are cars also purchased from other dealers and/or brought into Nickey for engine swaps, after they had been sold/ driven and/or raced.
I do have to mention that I am not a fan of "Fake" paperwork such as the build sheet you plan to reproduce. Even if it is used for display pouposes only. I can't tell you how many such documents I look at every year which misslead or confused some one!
Take the real documents you have, along with the affidavit and display those along with a breif history and the Hobby will be much better off in the long Run.
I hope this helps. I look forward to seeing the Car at the Vette Fest, See you at there