Just saw this post on a Beatles forum about Carl's song "My old friend". The link doesn't work anymore but the part was copied and pasted by a member of that board. So thanks for that.
Before that, here's an interview that Bobby Bare did with Carl Perkins. At the end, Carl plays a short, heartbreaking solo version of the song. Go to 7:30 mins if you don't want to cath the rest of the interview:
http://www.youtube.com/watch?v=sHH-4q8kA00http://www.daytrippin.com/lennon65.htm (a little less than halfway down the page)
In 1981, just after John Lennon died, Paul and Linda invited Carl to stay with them in Montserrat. Paul wanted Carl's help recording a song called Get It for his new album, Tug Of War. Carl spent eight days with them, and George and Ringo had been there to help out as well. It was a great time between old friends who had shared such a legendary musical past.
The night before he left, a song came to Carl that summed up his warm feelings about the visit, and he couldn't get it out of his mind. It was so strong that Carl didn't even write it down, which was strange for him. He usually always wrote his songs down immediately.
In the morning, Carl Perkins sang the song, which he named My Old Friend, for Linda and Paul, saying it was his gift for having him as a guest. Half way through the song, after singing "if we never meet again this side of life, in a little while, over yonder, where there's peace and quiet, my old friend, won't you think about me every now and then?" tears streamed down Paul's face and he stood up and stepped outside.
Not knowing what the matter was, Carl stopped and Linda put her arms around him, thanking him for helping Paul to connect with his grief over John Lennon's death. Now this next part was not in the video, but according to the book, Linda explained that the last time Paul talked to John, he had said the same line to Paul, "think of me every now and then, my old friend."
Carl had no doubt that the song was from John Lennon, as a gift to Paul.
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Another site said a couple months before John died Paul and Linda visited him and thats when John said it, patting Paul on the shoulder as he did.