Did Elvis Aron Presley legally change his middle name to Aaron before he died?

Did Mr. Elvis Presley go into a legal place and legally changed his middle name to Aaron before he died? If not, then his middle name is Aron according to what is written on his birth certificate and the spelling on the tombstone is wrong. In order for that middle name to be on his tombstone. Elvis would have to have legally changed his middle by turning in his birth certificate. Did he do that?