As far as I know, the only kit ever produced of the USS JFK was by Monogram back in the early 1970s. I don't recall the scale, but it was about 16" long.
The Kennedy is unique in that it has an oddly angled stack on the island, and the Monogram kit is the only one I am aware of that has this represented correctly.
Ironically, Monogram has re-issued the kit as several other carriers, which is nonsense due to that very stack detail.