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IJA tanks are a focus of mine and I have built and painted many. See my How To Paint An IJA Tank as a ready reference guide. In it I highly recommend the Hataka Orange Line Lacquer IJA set.
They are excellent paints and are the best out of all the IJA sets on the market. I have used them all. I did experience tip dry and clogging with the Vallejo set, which can be alleviated with retarder and flow aid, but the Hataka set shoots superbly right out of the bottle. Harvey Low’s AMPS presentation that Frenchy linked to is an excellent guide through all the color combinations and patterns throughout the war. Also, I have the complete AJPress series on IJA armor so if you have any questions on colors or patterns, feel free to ask.