OK here goes
Green 5 stripe--6
Red 5 stripe-----3
Green single stripe-2
Silver red stripe----1
Interestingly I am not sure a NJ Transit unit was manufactured on O gauge.
In the prototype, most GG1s wore the Green 5 stripes for the longest period 20 years or more. The Green single stripe lasted from 1955 through 1970 or so into the PC era, about 15 years. Amtrak colors from 1971 through early 1980's about 10 years or so.The red units were about 10 or so and the silver PRR only 3.
Color photography became popular in the postwar period and affordable in the 1950s so the most photographed in color are likely the PRR single stripers and the PC and Amtrak in black.
I believe there are about 25 or so GG1s surviving today and none operational