HI, I have set up many PB's
1- initialise at 150 %travel on your 4 channels
2-Reversing, keep at 150% and use the servo that is going in the right direction as your base servo(example A1)
3-Always remove servos from jet and place side by side
4-plug second servo into A2 socket and reverse 90degrees at a time ( left then right, or up then down )
5-check travel and fine tune.
6- reduce travel, 125 is safe.
7-if you do not reduce the travel, the reversed servo, at max travel, could rotate 180 degrees, causeing #"*^#??
Rcpete