Sir Paul McCartney stopped by The Late Show on Monday night (Sept. 23) to chat with host Stephen Colbert about his children's book Hey Granddude!, loving Elvis and, most importantly to revisit the spot where The Beatles first played in America on the Ed Sullivan Show stage more than 55 years ago. And while he couldn't remember the exact spot where the band set up all those years ago, McCartney did remember how nervous the lads were back in the day.

"It doesn't show too much when I look at it now I think, 'we don't look nervous at all!,'" McCartney said. The legendary rock icon touched on a variety of topics in the pre-taped interview that ran on the night Colbert was flying back from Sunday night's Emmy Awards. From the early songwriting inspiration he took from his family's boozy standards sing-alongs in the living room to the devastating loss of his mother when he was 14 and ticking off his favorite Beatles covers over the years.

After asking someone to get him the top 10 all time covers of "Yesterday," McCartney said his favorites included versions by Frank Sinatra, Elvis Presley, Ray Charles and his favorite, Marvin Gaye. "The funny thing about Sinatra, Marvin and Elvis they changed the words," he said. "In the middle I say, 'I said something wrong, now I long for yesterday.' All of them said, 'I must have said something wrong,' they're not owning up!"

Colbert asked if McCartney was aware that K-pop megastars BTS had done their own Beatles homage on The Late Show earlier this year -- during which they sang an impromptu round of "Hey Jude" -- which Macca gave a hearty round of applause to as the host wondered what it was about the Beatles that transcends all language barriers? "Easy lyrics?" McCartney joked.

Things got a bit serious as well, with McCartney trying to explain the difficulty of squaring his global, eternal fame and people's reaction to meeting him with his vision of himself as just another guy "slobbing" about in front of his TV like the rest of us. When Colbert noted that the solo Apr. 1974 McCartney and Wings hit "Band on the Run" has an "enormous emotional resonance" for him since it represented the last happy summer he can remember because his father and two brothers died in a plane crash that September.

"I know that you have nothing to do with what that emotionally means for me, but what do you do knowing that lives inside of other people when they see you? How do you deal with a fan who comes up... how do you deal with me right now telling you that?" Colbert said as McCartney cut the tension with his signature wit. "It's not easy, Stephen. I was a fan of lots of people, so I kind of get it. I'm also very happy that songs that I just wrote originally just to make some money... but the fact that these songs then get into people's heads and they have this meaning. That's the biggest bonus you can have."

After McCartney noted that Lennon also lost his mother at an early age, Colbert asked if he still thinks of his songwriting partner, which he says he does "quite often... I dream about him. When you've had a relationship like that for so long, such a deep relationship, I love when people revisit you in your dreams," he said. "I often have band dreams. I have a lot of dreams about John."

McCartney also plugged his new children's book, inspired by his grandkids, with Colbert suggesting a few other titles he might consider for follow-ups, including: Gran On the Run, All You Need is Love and Lipitor, Help! I've Fallen and I Can't Get Up", Back in the AARP and Ob-La-Di Obl-Adult Diaper.