Having a few more pages to fill when comics reversed their shrinking page-count in 1980, Marvel split the Ant-Man story from TALES TO ASTONISH #40 (1963) in two issues of MGC behind post-Kirby FF reprints. This issue has the first six pages (with the last edited slightly, removing two panels to allow for the statement of ownership, which reveals that in 1980 an about-to-be-cancelled book reprinting 10-year-old FF stories could sell almost 100,000 copies a month).
This first part sets up the story of a series of mysterious truck hijackings, which Ant-Man hears about when he gets a signal transmitted from a series of ants. No really. And it gets better, to one of the most beautifully absurd scenes in a 1960s Marvel comic (and there are a lot to choose from). To get to his destination, Ant-Man shoots himself out of a gun, and has a group of ants converge to cushion his fall. Only he overshoots, almost hits a brick wall head-on, but for the quick thinking of his loyal ants.
Man, that's just crazy. The rest of the story sets up Ant-Man's plan to capture the hijacker, only to find himself suddenly taking ill (and riding an ant to a doctor), leaving the truck defenseless. These early Ant-Man stories aren't the best, but they do have some great scenes, and give Kirby a chance to do some weird perspective shots and of course lots of ants.
Sol Brodsky inks this story, one of the few non-cover examples of him inking Kirby (the other more notable one being FF #3 and #4). It's very nice, a shame he didn't do more inking of Kirby back then. I'm only judging from reprints, so maybe I'm wrong, but he seems to be among the closest to how Kirby would have inked the work himself.