Hey, Larry! Nice post and pictures. That's quite a haul of Ralph Terry. Were he still alive, I know he'd be very amused.
You mentioned Post Grape Nuts Flakes. That geriatric cereal was tied to a pair of chapters in my book, NEVER CHEAPER BY THE DOZEN. One chapter concerned the initial Post offering from 1960, whilst the other figured heavily concerning a pair of stalwarts from their last set, 1963. I had a lot of fun, and put a great deal of effort into writing my book.
If you don't already own them, please do try to hunt down a copy of Dan Mabey's Post Cereal books. Dan put SO MUCH research and photos into each of them. They are hard to find now, and very expensive, as they should be for what he put into them. Like mine, they aren't the kind of tome you'd ever find at Barnes 'n Noble.
Happy hunting, Larry.
--- Brian Powell