I see. the main problem with getting ID if a Mig-3 was the early or late is that a pic of a cockpit can't be the source. Just these looked there the same or almost the same. I would say the difference between the MiG-1 and MiG-3 cockpits should be better noticed than between the late and early MiG-3 ones. So the only way to make the ID correctly are images of the external appearance of the entire planes.
Here is a shot of the caption "early Mig-3" as well..
Here is a shot of the caption "early Mig-3" as well..