Complex sentence: During this time, he worked on numerous projects including two songs with Elvis Presley: "Don't Cry Daddy" in 1969 and "Kentucky Rain" in 1970.
Split into simpler sentences: During this time period, he worked on numerous projects; including two songs with Elvis Presley. The first, "Don't Cry Daddy", in 1969; and the second "Kentucky Rain" in 1970.