No, it was not actually the guy pictured working on the bike, that did the prep work, and retained the master cylinder for near 40 years.
Nice thought Ash, re-uniting the bike with the master cylinder. Since the first day i saw that bike at the back of a shed back in '87, it has for me remained the ultimate CB750 to aspire to own. 27 years on, that daydream persists!
Cheers - Chris R.