You can call or email Mr. Raffaele Ludovico at RS corse in Modena, he has the original books with registry numbers from the factory. That's how I confirmed the numbers when I bought my pushbutton, including original color.
The web site is www.recorse.com, the email is
chiara.rscorse@gmail.com
He's a very nice and available gentleman, very knowledgeable and ex mechanic for DeTomaso when it was still open. There may be a fee for the research of the numbers, but I may be wrong.
Cheers.
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