I’m not sure why this page is labelled page 8 on the margins of the original artwork, because you can see it’s listed as page 7 in the right-hand corner of the art, and that’s where it appears in the story. Maybe this was originally page 8 and Stan Lee eliminated a page.
Over the years there’s been much speculation and controversy surrounding the Kirby/Lee working method. Apparently Lee never gave Jack a script, so it was Kirby’s responsibility to write the bulk of the stories using visuals. So the question becomes: how did Kirby communicate certain details to Stan Lee? In my opinion, I suspect Jack would meet with Lee probably in Lee’s office, then Jack would show him the artwork, and quickly verbally go through the story with Lee. I think that is why you frequently see small notes in Stan Lee’s handwriting from 1960 – 1963 concerning character dialogue, scribbled on the margins of the original artwork.
For example, below panel 6 on this page, Stan Lee has written “We need help.”
My guess is that Jack explained this page to Lee, and during that process Lee quickly made this note to himself — as you can see looking at the artwork that note nicely sums up the panel above it (panel 6). This would have made it easier for Lee to dialogue the book later because he would have these little sign-posts to help him remember what Jack intended to take place in certain panels or sequences of the illustrated story.
This note below panel 7 appears to be a note to Sol Brodsky: “Fix boy’s hair.” Stan seems to think something is wrong with the hair on one character. He is also is making it clear he wants the tails of the word balloons to point at the central character. Note this text is larger and in all-caps, easier for a production assistant to read.
Below panel 8 is another example where it looks like Lee made a note to himself, probably during a discussion with Kirby: Stan was simply making it clear to himself that the character in the image above the note is “Tony Stark.”
You can also see Jack signed this page, so in all likelihood this was one of the books returned to Jack in the 1980s when Marvel returned 2/5 of his original artwork.