Matching number GPAs

[Donovan]

I was reviewing Gavin Walkers website (willysma.com) that has developed a list of known GPAs. I went through the list and only found 14 GPAs with matching numbers (have original engine, frame, and dash plate)! Is this accurate or are there matching number GPAs missing from his list. It looks low to me and I was curious on others opinions.
Thank you,
Donovan