Actually, K0's (after serial # 1007414) share more parts w/ late sandcast motorcyles than the early sandcast's share w/ late sandcast's. The early sandcast's much more unique in their details. Frame is different (headstock bracket), as well as exhaust clamps (much chunkier), carbs (thinner cables and caps), choke lever (longer), airbox (smaller brackets w/o rubber packing), horn (left side on early and sometimes grey), rear hub (2 internal holes instead of 4), oil filter cover (smooth on early), gauge numerals (subtly different color and detail), gauge rubber mounts (locating pip), front brake hoses (short, straight necks), fuel tank (different shape underneath), centerstand (simpler), exhaust baffles (fatter), candy blue-green paint (early sandcast's were more green in color); and there are many more. The point is, Honda did not make wholesale changes when they went to diecast, they made changes constantly, 1 or 2 at a time from the very earliest releases. The EARLIER the sandcast, the more unique it is. Honda Parts Manual does a good job of cataloging these changes. And not everything "etched in stone" either; I've come across some "not correct" details on unrestored bikes. I am very lucky recently to have found an early, all-original, unrestored sandcast that is straight as an arrow and untouched since new, and will remain in that state of grace as long as I own it (I'm resisting even washing it, - bike has a superb patina). It will be the subject of a photo essay w/ detailed documentation of all this good stuff, someday.