I've got a '76 Yamaha Moto-Bike myself.
I've also got a '79 Mongoose that I've owned since about '81. Back in the day, I customized it to my liking. I painted the frame gloss black, got black Tuff Wheels, blue gumwall Snake Bellys, and blue everything else.
I've kept it all this time and recently started restoring it, but not to original, to the way I had it. I feel it's just as "legit" because all the aftermarket parts on it are from the bike's era.
Most people's dilemma is whether to restore to stock or to how they had it, like your awesome "Yamasaki" jump bike.
I've got a new dilemma.
I'm starting to want to restore my bike to how I'd like it now, instead of how I had it.
I got a set of Motomags for it (that I'm giving a full polish) because that's what I really always wanted, and I am thinking of candy blue powdercoat instead of my rattle can gloss black.
It's still my original high school bike, even if I change the color and change the wheels, right?
P.S. Holy cow I can't believe how much money a nice '79 Goose with Motomags is worth now!! Too bad I can't ever sell this one!
The Yamaha... I'm less attached to it, the prices I've seen are pretty tempting!
It's stock and compare to the reflectors, minus the chain guard.