Brian,
The Nemeth Code calls this type of notation "non-simultaneous superscripts and subscripts". See Section 82.b of the 1972 Nemeth Code. A baseline indicator comes to the rescue. By inserting dot 5 before each non-simultaneous superscript or subscript, you will indicate to the reader that they are to be read left-to-right because you are returning to the baseline before indicating the next superscript or subscript. Here is the transcription of the image you provided.
_% ,R;I"^J";KL _:
Lindy