If you're using a computer radio (and I assume you are with multi servo setups) you can program the Tx to reverse one of the elevator servos- you don't need a reverser. There is also a reversing "Y' adapter that will do the same thing, or you can make your own --just clip and reverse the power wires(black and red on Futaba) on one servo lead downstream of the Y. You don't need but a mm. of clearance between the servo arms , but I like all my servos "pointing" the same way.