Hi guys,
Just thought I'd add my little bit of knowledge of this area of Boeing operating manuals, now known as AFM and FCOM.
The AFM, the highest authority as far as Boeing FCOMs is concerned, has an applicability section in it's preface. This specifies the actual airplanes by their manufacturing serial numbers that the AFM refers to, and adds that no other airplanes are included.
It's all related to FAA approvals.
Cheers...FD