Trying to research Sir Paul's contact with Stan Lee, co-creator of characters like Spider-Man, Iron Man, the X-Men and Avengers.
Lee's recent "graphic memoir" called Amazing, Fantastic, Incredible showed a meeting between the men in London in the 1970s. Sir Paul, apparently, called Stan during one of his trips to the UK to launch a comic.
The second meeting was fairly recently, at a Superbowl. Here's the only photo I have seen from any of the two meetings.