Complex sentence: Harrison originally wrote the song (with different lyrics) for Ringo Starr to record, but after Lennon's untimely death the lyrics were changed to reflect a tribute to Harrison's lost friend and colleague.
Split into simpler sentences: Harrison originally wrote the song (with different lyrics) for Ringo Starr to record. George took the track back and after Lennon's untimely death the lyrics were changed to reflect a tribute to Harrison's lost friend and colleague.