Yes, after a consult with other experts, I discovered that the measurement for the width of the narrow fuller should be 7mm. My "shallow fuller" measured 8.5mm. That puts it right smack in the middle. The standard is 10mm. Yes, it is narrower and shallower than the standard fuller, but no matter what it is, it probably is not the famed shallow fuller. It still would be a nice collectable LanCay M9, but not for the $360 I paid. I sent it back and received a full refund. I would recommend this seller very highly. Thank you all for the valuable input.
Marv
PS. I am also selling the other M9 I used for comparison.