Simplify the following text for a Grade 8 native English-speaking person.
Original: Britten originally wanted the part of Billy Budd to be sung by Geraint Evans , but Evans found that the notes were too high for his voice , so he sang a different role , and the role of Billy Budd was sung by Theodor Uppman .
Simplified: The title role was originally reserved by Britten for Geraint Evans , who prepared it but then withdrew because it lay too high for his voice . Britten chose Theodor Uppman to replace him , and Evans sang a different role , Mr Flint .