My favorite McCartney bass track is on my favorite Beatles song: "I Saw Her Standing There." It's his take/warp on the "I'm Talking About You" bass part. It's nothing but groove; it isn't technically mind blowing or anything. Great part is that you can pan to get pretty much nothing but Ringo and him prominently. One hell of a rhythm section, even that young. I'm also quite partial to this little ditty. I heard it the first time, and thought it was a Jah Wobble solo song I had never heard before.