This song by Elvis Presley is in C.
The G7 at the end of Part 3b is to bring the song back to Part 1a, i.e., you only play the G7 if you repeat the song.
These are the “cheat” chords I played…
Part 1a: CM7 - Em - Am
Part 1b: C - C7 - F
Part 1c: G7 [...]
