The major difference between the A6M2 and the A6M3 model 22 was the engine from Sakae 12 to Sakae 21.
Also, there were two variant of the A6M3 model 22. One was with short barrel 20mm cannons and the other with long barrel as model 22-KO.
About 580 A6M3 model 22 were manufactured but most of them were model 22-KO.
Shinpachi, Got it, thanks! And another question - after the Junkers-88, I plan to build A6M2 from Tamiya, 1:32. Is it true that the production of Mitsubishi Zero had niches main gear colored aircraft, not aotake?
Mitsubishi Zero: Light Grey for the wheel bay and the landing gear cover
Nakajima Zero: Aotake for the wheel bay/bay cover(inside) and Light Grey for the landing gear cover
Light grey was Navy J3.
Here is a navy color sample book I reproduced in CGI ten years ago.
Just for your references