Fred Hembeck, in his Dec 10th entry, has a note from Mark Evanier mentioning that the MavelMania catalog cover Fred had posted last week was, in fact, inked by Kirby himself, and posts a FANTASY MASTERPIECES cover that Kirby inked, as well as the Bullpen hype that specifically mentioned that fact. I'd agree with Fred that it does look a lot like Giacoia's inks of the period (such as a few of the other issues of FM around that), which I guess just means Giacoia was pretty faithful to Kirby's pencils.
That reminded me that it was in facted hyped even earlier than that, in this item from FF #45 in 1965, about 8 months before that FM cover:
I think I recall Mark Evanier once posting somewhere that the last full story Kirby inked (as opposed to covers like this and poster/pin-up stuff for MarvelMania) was a western for Marvel in the early 1960s, but I'm not sure which one that would be. Anyone?