A new lease on old parts can be great if the part is worth saving and designed to be serviceable. Just because something is old doesn't mean it is worth saving, a BB like that is designed to be replaced. If you want a serviceable BB go for loose ball or a Phil Wood.

Certainly you could get a new one and play around with the old one but generally if Sugino is saying don't do it, there is probably some good reasoning. Yes sometimes manufacturers say things because of liability but their reasoning is generally rooted in bad ideas that consumer have tried or might try.

People try to adjust bearings in a Dynamo hub and wonder why the thing doesn't work right afterwards even though all the manufacturers and many experts who sell them also say the same thing. People love to think that someone who does it for a living is wrong. If one believes the experts are wrong why even ask them? I never understand that.