I just stumbled upon this resource from the Pianoforte Tuners' Association in the UK. Several manuals plus a parts list and tool catalogue, both of which I was unable to find directly from Yamaha's site. About 12 years old but the parts numbers that I checked are correct. Since Yamaha is increasingly hard to actually talk to, knowing the part numbers enable one to order online without waiting for them to get back to you as I have all week.
Worth perusing their site, their convention is coming up and they even have a distinguished lecturer from the PTG.
https://pianotuner.org.uk/yamaha-files/
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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
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