This question is based on using one TX/RX channel for dual servos on elevator.
I have read that often a reversing Y harness will not give equal throws in this application and that internally reversing the servo is a good option.
The general instructions seem to be (for a brand(s) other than yours) is two steps, 1) reverse the wires on the motor; 2) reverse the two outside wires on the potentiometer.

.Questions: 1) Which of your servo series lend themselves to this type of reversing? (edit: found another page your servo site, appears all your servo Have SMT ,motor to circuit board hard wired.)

1A)Does Futaba offer reversed servos or a free service to reverse them?

2) The SR10 has a centering adjustment, but will it provide equal throws (travel distance) both directions?

If there is another good solution please elaborate.