Wish my GTR parts book had specified these were for GTO only!
Those two parts baffled me for a long time when I bought another GTR having had one back in 69.
You will find there are many minor errors and anomilies all through the GTR/GTO manual and parts book. My original GTR manual had a full paragraph which explained that the alternator turned at half engine speed and how it affected the points and cam arrangement. WRONG, it turned at engine speed. I now know this paragraph had been copied and pasted from the earlier 175 manual and was corrected in later reprints.
Have a look through the 175 manual, you will find it is far more comprehensive and informativel. BS were rightly proud of their machine and wanted the owner to fully understand how it worked.
By comparison, the GTR manual is a minimum effort affair. Cobble something together so we can get these bikes on the market ? Were BS questioning the future of their bike production when the GTR was launched ? I believe that was the case.
Just my opinion, Brian.