MOG

I love this one! Here is some info on it:

The master take was recorded on 31 January 1969, as part of the 'Apple studio performance' for the project Get Back. McCartney played piano (aBlüthner Flügel from Leipzig), Lennon played bass, Billy Preston played organ and George Harrison and Ringo Starr assumed their conventional roles.^[6]This performance, in which Lennon and Harrison harmonised with McCartney's lead vocal and Harrison contributed a subdued guitar solo, can be seen in the film Let It Be.

On 30 April 1969, Harrison overdubbed a new guitar solo on the best take from 31 January that year.^[7] Harrison reportedly overdubbed another solo on4 January 1970. The first overdub solo was used for the original single release, and the second overdub solo was used for the original album release. Some fans mistakenly believe that there were two versions of the basic track - based mostly on the different guitar solos, but also on some other differences in overdubs and mixes.^[8]