Herb,
There are 2 problems: The layout and the playback.
THE LAYOUT:
In the reed section you have 5 staves:
1. clarinet
2. alto
3. first tenor
4. second tenor
5. baritone
and you want to substitute a second alto for the second tenor:
1. clarinet
2. first alto
3. tenor
4. second alto
5. baritone
In the staff attributes for staves 2, 3 and 4 you have to change the staff name. In the staff attributes for staff 4 you also have to change the transposition from tenor to alto. You might also like to re-arrange the staff order to
1. clarinet
2. first alto
4. second alto
3. tenor
5. baritone
- and don't forget to sort staves when you have re-arranged the staff order.
THE PLAYBACK
In the instrument list you might like to change the instrument for staff 4 from tenor to alto. If independent volume is important, don't re-use the alto used for staff 2, but rather create a new instrument - another alto - assigned to another channel than the first alto.
Peter