First, let me say that I am not a music transcriber, so if anything I say conflicts with the music code, please let me know.
You can use the grade 1 word indicator if you want grade 1 mode to apply to more than one symbol. So if you have more than one superscript within one symbols sequence, use the grade 1 word indicator and you are then in grade 1 until the space. You would not need an additional grade 1 indicator within that same symbols sequence. Just remember that you are in grade 1 mode...so no contractions are allowed. To terminate grade 1 mode before a space, use the grade 1 terminator. Also keep in mind that the numeric indicator also sets grade 1 mode. In the example you show below [(6)(14)(56)(35)(3456)(124)] if you had an additional superscript following the number, you would not need the grade 1 indicator before that superscript.
Let me know if you have any further questions!