STILL can't decide if I think it is an Olympic 12 or an International, but lately I have been leaning toward International.
Was finally able to start working on it today, cleaning and adjusting. After removing the rear wheel and cleaning the derailers and freewheel I saw that it has a Suntour Perfect 6-speed freewheel (that cleaned up beautifully, looks almost new!) and forged Suntour rear dropouts.
I know that sometimes the type of dropout gives a clue as to what the bike is (forged vs. pressed), but I can't find anything online for a 1980 Nishiki to tell me if the dropouts between the Olympic and International were different.
Any more thoughts or ideas? If I can't decide for 100% sure I think I am going to dub it an International.....