Okay, let’s go back to the start.. or nearly to the start.
Here’s the first GA I have that mentions Walt. This is from “The Rectangle”, which was Frank King doing an entire page of various comics, of which I’ve cropped out the Alley panel. The original gang looked to be more like 8 guys, but it mentioned Doc by name at the start, and also has a prototypical Avery and Bill, at least to my eye in the right foreground.
December 15, 1918 – https://i.imgur.com/IoKcM44.jpg
And then two weeks later, I feel I have to include this one just for the “new moon over my left shoulder” bit, heh. (Walt with the overalls and porkpie hat rather than his sailor cap.)
December 29, 1918 – https://i.imgur.com/oaNUoFr.jpg